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Type-5 phosphodiesterase inhibition in the prevention of doxorubicin cardiomyopathyFisher, Patrick William, January 1900 (has links)
Thesis (Ph.D.) -- Virginia Commonwealth University, 2005. / Title from title-page of electronic thesis. Prepared for: Dept. of Physiology. Bibliography: p. 81-91.
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Eficácia da associação de tadalafila e fluoxetina de liberação lenta no tratamento da ejaculação precoce / Efficacy of tadalafil associated with once-weekly fluoxetine in premature ejaculationMattos, Rogério de Moraes 12 August 2005 (has links)
Introdução e objetivos: A ejaculação precoce é uma forma de disfunção sexual presente em 25,8% dos homens brasileiros. O objetivo do presente estudo é avaliar se a associação de tadalafila, um inibidor da fosfodiesterase-5 e fluoxetina, um inibidor da recaptação da serotonina em uma apresentação de liberação lenta, ambos tomados uma vez por semana, pode prolongar o tempo de latência da ejaculação em homens com ejaculação precoce. Pacientes e Métodos: Sessenta pacientes com ejaculação precoce e sem disfunção erétil foram avaliados. A idade média foi 45,5 anos de idade (desvio padrão +/- 9,6). O tempo médio de ejaculação antes do início do tratamento era 51,3 segundos (desvio padrão +/- 23 segundos) e não foi estatisticamente significativo entre os grupos (p=0,805). Foram distribuídos de forma aleatória e duplo-cega em 4 grupos, conforme a medicação recebida: (1) fluoxetina 90 mg e placebo, (2) tadalafila 20 mg e fluoxetina 90 mg, (3) tadalafila 20 mg e placebo, e (4) placebo com placebo. Antes de iniciar qualquer medicamento, os pacientes anotaram o tempo de latência para ejaculação com um mesmo cronômetro uma vez por semana, durante 3 semanas. À partir do início do uso dos medicamentos, os pacientes cronometraram o tempo em nove ocasiões, uma vez por semana. Foi usado fluoxetina 90 mg ou placebo semanalmente e tadalafila 20 mg ou placebo em um intervalo de até 36 horas da presumida relação sexual com parceira heterossexual regular. Os pacientes foram prospectivamente seguidos a cada 3 semanas durante 12 semanas. Resultados: A comparação dos grupos com análise de variância (ANOVA) unidirecional demonstrou diferença estatisticamente significativa no tempo de ejaculação após tratamento (p<0,001). O maior aumento em relação ao tempo basal foi observado no grupo que associou tadalafila 20 mg com fluoxetina 90 mg semanalmente (p<0,001). Reações adversas foram observadas, tendo sido toleradas e equivalentes entre os grupos usando princípio ativo. Conclusão: Tadalafila 20 mg utilizada em um período de 36 horas de atividade sexual associado com fluoxetina 90 mg de liberação lenta usada semanalmente, significativamente aumentou o tempo de latência de ejaculação em homens com ejaculação precoce, quando comparados com cada droga usada isoladamente, beneficiando esses pacientes sem a necessidade do uso diário de medicamentos. / Introduction and Objectives: Premature ejaculation is a sexual disorder present in 25.8% of brazilian men. The aim of the present study is to evaluate if the association of tadalafil, a phosphodiesterase-5 inhibitor and fluoxetine, a selective serotonin reuptake inhibitor in a slow release presentation, both taken once a week, can prolong the intravaginal ejaculatory latency time (IELT) in men with premature ejaculation. Methods: Sixty patients with premature ejaculation and no erectile dysfunction were enrolled in the protocol. Mean age was 45.5 years (range 24 - 64 years, standard deviation +/- 9.6). They were randomly assigned in a double-blind manner into 4 groups to use the medications: (1) fluoxetine 90 mg and placebo, (2) tadalafil 20 mg and fluoxetine 90 mg, (3) tadalafil 20 mg and placebo, and (4) two different placebo capsules. Before starting any medication, each individual timed the IELT with a given stopwatch in 3 different days, and likewise weekly during the treatment period. Mean IELT before starting treatment was 51.3 seconds (sd: +/- 23 seconds), and was not different between groups (p=0.805). They took fluoxetine 90 mg or placebo once a week, and tadalafil 20 mg or placebo in a 36-hour frame of intended sexual intercourse with a regular heterosexual partner. Patients were prospectively followed every 3 weeks during a 12-week interval. Results: Comparison between groups with oneway ANOVA demonstrated a statistically significant difference in post-treatment IELT (p<0.001). The greatest increase in time from baseline IELT was observed in patients in the tadalafil plus fluoxetine group (p<0.001). Side effects were observed and tolerated, being equivalent in groups using active drugs. Conclusion: Tadalafil 20 mg taken in a 36-hour window for sexual intercourse associated with fluoxetine 90 mg in a slow release form taken weekly, significantly increased the intravaginal ejaculatory latency time from baseline in men with premature ejaculation, when compared to either drug taken solely, benefiting patients without the need to be medicated on a daily basis.
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Eficácia da associação de tadalafila e fluoxetina de liberação lenta no tratamento da ejaculação precoce / Efficacy of tadalafil associated with once-weekly fluoxetine in premature ejaculationRogério de Moraes Mattos 12 August 2005 (has links)
Introdução e objetivos: A ejaculação precoce é uma forma de disfunção sexual presente em 25,8% dos homens brasileiros. O objetivo do presente estudo é avaliar se a associação de tadalafila, um inibidor da fosfodiesterase-5 e fluoxetina, um inibidor da recaptação da serotonina em uma apresentação de liberação lenta, ambos tomados uma vez por semana, pode prolongar o tempo de latência da ejaculação em homens com ejaculação precoce. Pacientes e Métodos: Sessenta pacientes com ejaculação precoce e sem disfunção erétil foram avaliados. A idade média foi 45,5 anos de idade (desvio padrão +/- 9,6). O tempo médio de ejaculação antes do início do tratamento era 51,3 segundos (desvio padrão +/- 23 segundos) e não foi estatisticamente significativo entre os grupos (p=0,805). Foram distribuídos de forma aleatória e duplo-cega em 4 grupos, conforme a medicação recebida: (1) fluoxetina 90 mg e placebo, (2) tadalafila 20 mg e fluoxetina 90 mg, (3) tadalafila 20 mg e placebo, e (4) placebo com placebo. Antes de iniciar qualquer medicamento, os pacientes anotaram o tempo de latência para ejaculação com um mesmo cronômetro uma vez por semana, durante 3 semanas. À partir do início do uso dos medicamentos, os pacientes cronometraram o tempo em nove ocasiões, uma vez por semana. Foi usado fluoxetina 90 mg ou placebo semanalmente e tadalafila 20 mg ou placebo em um intervalo de até 36 horas da presumida relação sexual com parceira heterossexual regular. Os pacientes foram prospectivamente seguidos a cada 3 semanas durante 12 semanas. Resultados: A comparação dos grupos com análise de variância (ANOVA) unidirecional demonstrou diferença estatisticamente significativa no tempo de ejaculação após tratamento (p<0,001). O maior aumento em relação ao tempo basal foi observado no grupo que associou tadalafila 20 mg com fluoxetina 90 mg semanalmente (p<0,001). Reações adversas foram observadas, tendo sido toleradas e equivalentes entre os grupos usando princípio ativo. Conclusão: Tadalafila 20 mg utilizada em um período de 36 horas de atividade sexual associado com fluoxetina 90 mg de liberação lenta usada semanalmente, significativamente aumentou o tempo de latência de ejaculação em homens com ejaculação precoce, quando comparados com cada droga usada isoladamente, beneficiando esses pacientes sem a necessidade do uso diário de medicamentos. / Introduction and Objectives: Premature ejaculation is a sexual disorder present in 25.8% of brazilian men. The aim of the present study is to evaluate if the association of tadalafil, a phosphodiesterase-5 inhibitor and fluoxetine, a selective serotonin reuptake inhibitor in a slow release presentation, both taken once a week, can prolong the intravaginal ejaculatory latency time (IELT) in men with premature ejaculation. Methods: Sixty patients with premature ejaculation and no erectile dysfunction were enrolled in the protocol. Mean age was 45.5 years (range 24 - 64 years, standard deviation +/- 9.6). They were randomly assigned in a double-blind manner into 4 groups to use the medications: (1) fluoxetine 90 mg and placebo, (2) tadalafil 20 mg and fluoxetine 90 mg, (3) tadalafil 20 mg and placebo, and (4) two different placebo capsules. Before starting any medication, each individual timed the IELT with a given stopwatch in 3 different days, and likewise weekly during the treatment period. Mean IELT before starting treatment was 51.3 seconds (sd: +/- 23 seconds), and was not different between groups (p=0.805). They took fluoxetine 90 mg or placebo once a week, and tadalafil 20 mg or placebo in a 36-hour frame of intended sexual intercourse with a regular heterosexual partner. Patients were prospectively followed every 3 weeks during a 12-week interval. Results: Comparison between groups with oneway ANOVA demonstrated a statistically significant difference in post-treatment IELT (p<0.001). The greatest increase in time from baseline IELT was observed in patients in the tadalafil plus fluoxetine group (p<0.001). Side effects were observed and tolerated, being equivalent in groups using active drugs. Conclusion: Tadalafil 20 mg taken in a 36-hour window for sexual intercourse associated with fluoxetine 90 mg in a slow release form taken weekly, significantly increased the intravaginal ejaculatory latency time from baseline in men with premature ejaculation, when compared to either drug taken solely, benefiting patients without the need to be medicated on a daily basis.
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Uso de diuréticos e de sildenafil em pacientes com insuficiência cardíaca crônica : revisão sistemática, metanálise e dados preliminares de ensaio clínico randomizado multicêntricoRosa, Priscila Raupp da January 2017 (has links)
A necessidade de buscar novos tratamento para a Insuficiência Cardíaca (IC) crônica levanta o questionamento da eficácia e segurança de drogas que não foram adequadamente testadas ou que ainda não tiveram sua eficácia aceita pela comunidade científica. O sildenafil é um vasodilatador com potencial eficácia na redução da pressão sistólica da artéria pulmonar (PSAP), mas com pequenos estudos e sem demonstração de impacto em desfechos duros. Os diuréticos de alça são utilizados rotineiramente em pacientes com IC sem sinais de congestão e tal prática não está recomendada nas diretrizes terapêuticas, desconhecemos sua eficácia e segurança neste cenário. No intuito de elucidar estas questões, foram desenvolvidos I) revisão sistemática com metanálise para estudo uso de sildenafil. II) revisão sistemática com metanálise para estudo uso de diurético de alça, III) Delineamento e execução em andamento de ensaio clínico randomizado multicêntrico testando a retirada de diurético de alça. I e II) Métodos e resultados: Ambas revisões sistemáticas foram realizadas no Pubmed, Embase e Cochrane, e termos relacionados à insuficiência cardíaca crônica diurético de alça e sildenafil foram utilizados, respectivamente. Após avaliação de texto completo, apenas estudos em humanos foram incluídos na metanálise. A droga sildenafil foi avaliada em 9 estudos randomizados contra placebo e demonstrou redução de hospitalização (RR 0.29, 95% C.I 0.11 to 0.78) e melhora progressiva em parâmetros funcionais e hemodinâmicos O uso de diurético de alça foi testado em 7 ensaios clínicos e não mostrou significância em piora da função renal, distúrbio eletrolítico e mudança de peso. III) Métodos e resultados: Em um estudo duplo-cego randomizado, de não inferioridade, multicêntrico compara-se o a segurança e tolerabilidade da retirada de furosemida de pacientes com IC crônica e estável com disfunção ventricular. Com início da coleta em setembro de 2015, até o momento 96 pacientes foram randomizados. Conclusão: Quanto ao sildenafil, já temos evidências que apontam para um efeito benéfico e progressivo na melhora da capacidade funcional, perfil hemodinâmico e redução de hospitalização em pacientes com IC com disfunção ventricular e pressão da artéria pulmonar elevada A recomendação para uso de diurético de alça em pacientes estáveis com IC permanece uma incógnita e o ensaio clínico em andamento nos trará uma resposta de importante impacto clínico na tomada de decisão para manutenção do uso de diurético. / The challenges and promises of new treatments for chronic heart failure (CHF) raises the question of the efficacy and safety of drugs that have not been properly tested or that have not yet had their efficacy accepted by the scientific community. Sildenafil is a vasodilator with potential efficacy in reducing pulmonary artery systolic pressure (PSAP), but with small studies and no demonstration of impact on hard outcomes. Routinely, Loop diuretics are used in patients with HF without signs of congestion and such practice is not recommended in the therapeutic guidelines, we do not know its efficacy and safety in this scenario. In order to elucidate these questions, I) systematic review with meta-analysis were developed to study the use of sildenafil. II) systematic review with meta-analysis to study the use of loop diuretics, III) Design and execution in progress of a multicenter randomized clinical trial testing for loop diuretic withdrawal. I and II) Methods and results: Both systematic reviews were performed in PubMed, Embase and Cochrane, and terms related to chronic diuretic heart failure of the loop and sildenafil were used, respectively. After full-text evaluation, only human studies were included in the meta-analysis. The drug sildenafil was evaluated in 9 randomized placebo-controlled studies and demonstrated a reduction in hospitalization (RR 0.29, 95% CI 0.11 to 0.78) and progressive improvement in functional and hemodynamic parameters. The use of a loop diuretic was tested in 7 clinical trials and did not show significant deterioration in renal function, electrolyte disturbance and weight change. III. METHODS AND RESULTS: In a double-blind randomized, non-inferiority, multicenter study, the safety and tolerability of furosemide withdrawal from patients with chronic and stable HF with ventricular dysfunction were compared. Randomization started at September 2015, to the moment 96 patients were randomized. CONCLUSION: Regarding sildenafil, we already have evidence of a beneficial and time-related effect on the improvement of functional capacity, hemodynamic profile and reduction of hospitalization in patients with HF with ventricular dysfunction and elevated pulmonary artery pressure. The recommendation for the use of a loop diuretic in stable patients with HF remains an unknown and the ongoing clinical trial will provide us with an important clinical impact response in the decision making to maintain the use of diuretics.
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Differential regulation of endothelial cell permeability by cGMP via phosphodiesterase 2A and phosphodiesterase 3A /Surapisitchat, James, January 2007 (has links)
Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 102-118).
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Uso de diuréticos e de sildenafil em pacientes com insuficiência cardíaca crônica : revisão sistemática, metanálise e dados preliminares de ensaio clínico randomizado multicêntricoRosa, Priscila Raupp da January 2017 (has links)
A necessidade de buscar novos tratamento para a Insuficiência Cardíaca (IC) crônica levanta o questionamento da eficácia e segurança de drogas que não foram adequadamente testadas ou que ainda não tiveram sua eficácia aceita pela comunidade científica. O sildenafil é um vasodilatador com potencial eficácia na redução da pressão sistólica da artéria pulmonar (PSAP), mas com pequenos estudos e sem demonstração de impacto em desfechos duros. Os diuréticos de alça são utilizados rotineiramente em pacientes com IC sem sinais de congestão e tal prática não está recomendada nas diretrizes terapêuticas, desconhecemos sua eficácia e segurança neste cenário. No intuito de elucidar estas questões, foram desenvolvidos I) revisão sistemática com metanálise para estudo uso de sildenafil. II) revisão sistemática com metanálise para estudo uso de diurético de alça, III) Delineamento e execução em andamento de ensaio clínico randomizado multicêntrico testando a retirada de diurético de alça. I e II) Métodos e resultados: Ambas revisões sistemáticas foram realizadas no Pubmed, Embase e Cochrane, e termos relacionados à insuficiência cardíaca crônica diurético de alça e sildenafil foram utilizados, respectivamente. Após avaliação de texto completo, apenas estudos em humanos foram incluídos na metanálise. A droga sildenafil foi avaliada em 9 estudos randomizados contra placebo e demonstrou redução de hospitalização (RR 0.29, 95% C.I 0.11 to 0.78) e melhora progressiva em parâmetros funcionais e hemodinâmicos O uso de diurético de alça foi testado em 7 ensaios clínicos e não mostrou significância em piora da função renal, distúrbio eletrolítico e mudança de peso. III) Métodos e resultados: Em um estudo duplo-cego randomizado, de não inferioridade, multicêntrico compara-se o a segurança e tolerabilidade da retirada de furosemida de pacientes com IC crônica e estável com disfunção ventricular. Com início da coleta em setembro de 2015, até o momento 96 pacientes foram randomizados. Conclusão: Quanto ao sildenafil, já temos evidências que apontam para um efeito benéfico e progressivo na melhora da capacidade funcional, perfil hemodinâmico e redução de hospitalização em pacientes com IC com disfunção ventricular e pressão da artéria pulmonar elevada A recomendação para uso de diurético de alça em pacientes estáveis com IC permanece uma incógnita e o ensaio clínico em andamento nos trará uma resposta de importante impacto clínico na tomada de decisão para manutenção do uso de diurético. / The challenges and promises of new treatments for chronic heart failure (CHF) raises the question of the efficacy and safety of drugs that have not been properly tested or that have not yet had their efficacy accepted by the scientific community. Sildenafil is a vasodilator with potential efficacy in reducing pulmonary artery systolic pressure (PSAP), but with small studies and no demonstration of impact on hard outcomes. Routinely, Loop diuretics are used in patients with HF without signs of congestion and such practice is not recommended in the therapeutic guidelines, we do not know its efficacy and safety in this scenario. In order to elucidate these questions, I) systematic review with meta-analysis were developed to study the use of sildenafil. II) systematic review with meta-analysis to study the use of loop diuretics, III) Design and execution in progress of a multicenter randomized clinical trial testing for loop diuretic withdrawal. I and II) Methods and results: Both systematic reviews were performed in PubMed, Embase and Cochrane, and terms related to chronic diuretic heart failure of the loop and sildenafil were used, respectively. After full-text evaluation, only human studies were included in the meta-analysis. The drug sildenafil was evaluated in 9 randomized placebo-controlled studies and demonstrated a reduction in hospitalization (RR 0.29, 95% CI 0.11 to 0.78) and progressive improvement in functional and hemodynamic parameters. The use of a loop diuretic was tested in 7 clinical trials and did not show significant deterioration in renal function, electrolyte disturbance and weight change. III. METHODS AND RESULTS: In a double-blind randomized, non-inferiority, multicenter study, the safety and tolerability of furosemide withdrawal from patients with chronic and stable HF with ventricular dysfunction were compared. Randomization started at September 2015, to the moment 96 patients were randomized. CONCLUSION: Regarding sildenafil, we already have evidence of a beneficial and time-related effect on the improvement of functional capacity, hemodynamic profile and reduction of hospitalization in patients with HF with ventricular dysfunction and elevated pulmonary artery pressure. The recommendation for the use of a loop diuretic in stable patients with HF remains an unknown and the ongoing clinical trial will provide us with an important clinical impact response in the decision making to maintain the use of diuretics.
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Uso de diuréticos e de sildenafil em pacientes com insuficiência cardíaca crônica : revisão sistemática, metanálise e dados preliminares de ensaio clínico randomizado multicêntricoRosa, Priscila Raupp da January 2017 (has links)
A necessidade de buscar novos tratamento para a Insuficiência Cardíaca (IC) crônica levanta o questionamento da eficácia e segurança de drogas que não foram adequadamente testadas ou que ainda não tiveram sua eficácia aceita pela comunidade científica. O sildenafil é um vasodilatador com potencial eficácia na redução da pressão sistólica da artéria pulmonar (PSAP), mas com pequenos estudos e sem demonstração de impacto em desfechos duros. Os diuréticos de alça são utilizados rotineiramente em pacientes com IC sem sinais de congestão e tal prática não está recomendada nas diretrizes terapêuticas, desconhecemos sua eficácia e segurança neste cenário. No intuito de elucidar estas questões, foram desenvolvidos I) revisão sistemática com metanálise para estudo uso de sildenafil. II) revisão sistemática com metanálise para estudo uso de diurético de alça, III) Delineamento e execução em andamento de ensaio clínico randomizado multicêntrico testando a retirada de diurético de alça. I e II) Métodos e resultados: Ambas revisões sistemáticas foram realizadas no Pubmed, Embase e Cochrane, e termos relacionados à insuficiência cardíaca crônica diurético de alça e sildenafil foram utilizados, respectivamente. Após avaliação de texto completo, apenas estudos em humanos foram incluídos na metanálise. A droga sildenafil foi avaliada em 9 estudos randomizados contra placebo e demonstrou redução de hospitalização (RR 0.29, 95% C.I 0.11 to 0.78) e melhora progressiva em parâmetros funcionais e hemodinâmicos O uso de diurético de alça foi testado em 7 ensaios clínicos e não mostrou significância em piora da função renal, distúrbio eletrolítico e mudança de peso. III) Métodos e resultados: Em um estudo duplo-cego randomizado, de não inferioridade, multicêntrico compara-se o a segurança e tolerabilidade da retirada de furosemida de pacientes com IC crônica e estável com disfunção ventricular. Com início da coleta em setembro de 2015, até o momento 96 pacientes foram randomizados. Conclusão: Quanto ao sildenafil, já temos evidências que apontam para um efeito benéfico e progressivo na melhora da capacidade funcional, perfil hemodinâmico e redução de hospitalização em pacientes com IC com disfunção ventricular e pressão da artéria pulmonar elevada A recomendação para uso de diurético de alça em pacientes estáveis com IC permanece uma incógnita e o ensaio clínico em andamento nos trará uma resposta de importante impacto clínico na tomada de decisão para manutenção do uso de diurético. / The challenges and promises of new treatments for chronic heart failure (CHF) raises the question of the efficacy and safety of drugs that have not been properly tested or that have not yet had their efficacy accepted by the scientific community. Sildenafil is a vasodilator with potential efficacy in reducing pulmonary artery systolic pressure (PSAP), but with small studies and no demonstration of impact on hard outcomes. Routinely, Loop diuretics are used in patients with HF without signs of congestion and such practice is not recommended in the therapeutic guidelines, we do not know its efficacy and safety in this scenario. In order to elucidate these questions, I) systematic review with meta-analysis were developed to study the use of sildenafil. II) systematic review with meta-analysis to study the use of loop diuretics, III) Design and execution in progress of a multicenter randomized clinical trial testing for loop diuretic withdrawal. I and II) Methods and results: Both systematic reviews were performed in PubMed, Embase and Cochrane, and terms related to chronic diuretic heart failure of the loop and sildenafil were used, respectively. After full-text evaluation, only human studies were included in the meta-analysis. The drug sildenafil was evaluated in 9 randomized placebo-controlled studies and demonstrated a reduction in hospitalization (RR 0.29, 95% CI 0.11 to 0.78) and progressive improvement in functional and hemodynamic parameters. The use of a loop diuretic was tested in 7 clinical trials and did not show significant deterioration in renal function, electrolyte disturbance and weight change. III. METHODS AND RESULTS: In a double-blind randomized, non-inferiority, multicenter study, the safety and tolerability of furosemide withdrawal from patients with chronic and stable HF with ventricular dysfunction were compared. Randomization started at September 2015, to the moment 96 patients were randomized. CONCLUSION: Regarding sildenafil, we already have evidence of a beneficial and time-related effect on the improvement of functional capacity, hemodynamic profile and reduction of hospitalization in patients with HF with ventricular dysfunction and elevated pulmonary artery pressure. The recommendation for the use of a loop diuretic in stable patients with HF remains an unknown and the ongoing clinical trial will provide us with an important clinical impact response in the decision making to maintain the use of diuretics.
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Associação de carbonato de londenafil (Helleva) e treinamento fisico na ereção peniana de ratos / Association of lodenafil carbonate and physical training in the penile erection of ratsPena, Clesio Borges 13 August 2018 (has links)
Orientador: Edson Antunes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade ce Ciencias Medicas / Made available in DSpace on 2018-08-13T10:46:39Z (GMT). No. of bitstreams: 1
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Previous issue date: 2009 / Resumo: A ereção peniana envolve a interação da estimulação neural do músculo liso do corpo cavernoso bem como liberação neuro-humoral de fatores contráteis e relaxantes do endotélio. A cascata de sinalização óxido nítrico (NO)/(GMPc) é o evento mais importante e efetivo no mecanismo de ereção peniana. Nesta última década, diversos inibidores de fosfodiesterase tipo 5 (PDE5) foram desenvolvidos e aprovados para o tratamento da disfunção erétil. Estes fármacos atuam inibindo a ação da PDE5 sobre o GMPc, que modula respostas fisiológicas em vários tecidos, como o relaxamento do músculo liso do corpo cavernoso. Dentre os inibidores de PDE5, são atualmente comercializados o sildenafil, tadalafil, vardenafil e o carbonato de lodenafil, sendo este último sintetizado no Brasil. Os objetivos deste trabalho foram: 1. Avaliar a eficácia do carbonato de lodenafil na função erétil de ratos, usando a técnica de pressão intracavernosa (ICP); 2. Avaliar o possível sinergismo entre o treinamento físico e o inibidor de PDE5 carbonato de lodenafil; e 3. Avaliar o efeito do carbonato de lodenafil, isoladamente, ou em associação com o treinamento físico na ICP de ratos submetidos (ou não) ao tratamento crônico com L-NAME. Ratos Wistar machos foram anestesiados com uretana (1,2 g/ Kg) por via intraperitonial. A seguir foi realizada uma traqueostomia para facilitar a respiração do animal, e a artéria carótida foi canulada para o monitoramento contínuo da pressão arterial média (MAP). Uma cânula provida de agulha foi inserida no corpo cavernoso esquerdo para registro da ICP, usando-se transdutores de pressão. A cavidade abdominal foi aberta expondo o nervo cavernoso esquerdo, localizado na região dorso-lateral da próstata. Um eletrodo bipolar de platina conectado a um estimulador foi posicionado sobre o nervo cavernoso. Estimulações elétricas do nervo cavernoso (pulso de 1 ms, 45 s, 6 V) a diferentes freqüências (2, 4, 6, 8 e 10 Hz) foram aplicadas. As alterações de pressão foram registradas em sistema PowerLab de aquisição de dados. A administração da droga foi realizada pela veia jugular. O treinamento físico teve duração de oito semanas, em sessões de uma hora por dia, cinco dias por semana. O grupo que recebeu L-NAME fez um treinamento físico preventivo de quatro semanas, e no início da quinta semana o L-NAME passou a ser administrado na dose aproximada de 10 mg/rato/dia, durante 4 semanas. Observamos que o treinamento físico em animais normotensos não alterou a pressão arterial média nem a pressão intracavernosa. O tratamento crônico com L-NAME aumentou a pressão arterial média nos animais sedentários. No entanto, este aumento foi atenuado nos animais submetidos ao treinamento físico. O L-NAME aboliu a resposta erétil (valores de ICP) nos animais sedentários. O treinamento físico não foi capaz de prevenir ou atenuar a queda da pressão intracavernosa induzida pelo L-NAME. O carbonato de lodenafil se mostrou eficaz em promover aumento da pressão intracavernosa tanto em animais sedentários bem como em treinados, no entanto, não houve sinergismo entre o treinamento físico e o carbonato de lodenafil. Adicionalmente, a associação entre treinamento físico e carbonato de lodenafil não foi eficaz em restaurar os valores de ICP em animais tratados com L-NAME. / Abstract: Penile erection involves an interaction between neural stimulation of the corpus cavernosum smooth muscle and neurohumoral contractile and relaxing factors released from the endothelium. The nitric oxide (NO)/cGMP pathway is the most important and effective mechanism of penile erection. In the last decade, phosphodiesterase 5 (PDE5) inhibitors were developed and approved for treating erectile dysfunction. These compounds
inhibit the PDE5, which deactivates the cGMP, responsible by several physiological responses in many tissues, such as the relaxation of the corpus cavernosum smooth muscle. To date, 4 PDE5 inhibitors are commercially available, sildenafil, tadalafil, vardenafil and lodenafil carbonate, the last one being synthesized in Brazil. The aim of this work was: 1) to evaluate the efficacy of lodenafil carbonate in rat erectile function, measured by the intracavernous pressure (ICP); 2) to evaluate whether the erectile responses of lodenafil carbonate are potentiated in exercised rats; and 3) to evaluate the effects of lodenafil carbonate, only, or associated to physical exercise in the ICP, in rats submitted (or not) to chronic treatment with L-NAME. Male Wistar rats were anesthetized with urethane (1.2 g/Kg, i.p.). It was performed a tracheotomy to allow the animal to breath, and the carotid artery was cannulated to continuously measure the mean arterial pressure (MAP). A needle coupled to a cannula was inserted in the left corpus cavernosum to measure ICP. The abdominal cavity was open and the cavernous nerve was exposed. A platinum bipolar electrode was placed on the cavernous nerve and connected to an electric stimulator. Electrical field stimulation of the cavernous nerve (pulses of 1 ms, 45 s, 6 V) under different frequencies (2, 4, 6, 8 e 10 Hz) were applied. Changes in the MAP and ICP were registered in a Powerlab¿ data acquisition system. Drugs were administered via jugular vein. The physical training program consisted in 60 min/day of running, 5 days/week and lasted eight weeks. In the group exercised which received L-NAME (10 mg/rat/day), LNAME administration started after the fourth week of training, during 4 weeks further. We observed that the physical training did not alter MAP and ICP in normotensive rats. Chronic L-NAME administration increased the MAP in sedentary rats. However, this increase was attenuated in trained rats. L-NAME administration blunted the increase in the ICP in sedentary rats and exercise was not able to prevent or attenuate this decrease in the ICP induced by L-NAME. Lodenafil carbonate was efficient in promote an increase in the ICP in both sedentary and trained animal. However, there was no synergism between lodenafil carbonate and exercise in producing increase in the ICP. Additionally, association between exercise and lodenafil carbonate was not able to restore the ICP in L-NAMEtreated animal. / Mestrado / Mestre em Farmacologia
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Role of second generation phosphodiesterase inhibitors on mammalian sperm mobilityMadamidola, Oladipo A. January 2015 (has links)
Over three decades ago, W.H.O. declared infertility as a public health issue; due to its impact on millions of people worldwide. While cases of infertility could be multifactorial (affecting both male and female), 50% of cases are due to male factor infertility and this is mostly characterised by reduced sperm motility (asthenozoospermia). Assisted Reproduction Technology (ART) is the only treatment option available for this condition. Over 20 years ago, non-selective phosphodiesterase inhibitors (PDEi), such as pentoxifylline, were shown to enhance motility of human spermatozoa; however, contradictory results and stimulation of premature acrosome reaction has precluded their clinical use. Advancement in our knowledge have now made it clear that human sperm express several different PDEs and these are compartmentalised at different regions of the cells. By using type-specific phosphodiesterase inhibitors, differential modulation of sperm motility can be achieved without affecting other sperm function such as acrosome reaction. Additionally, by enhancing sperm function through PDE inhibition, there is a possibility of increasing IVF rates. The objective of this thesis is to: (1) examine the effect of phosphodiesterase inhibitors on spermatozoa in order to identify compounds that have clinically relevant enhancement of human sperm motility; (2) identify the signalling pathway(s) involved in the motility enhancing effects of identified compounds by targeting the modulator and mediator of cyclic nucleotides; (3) develop an animal IVF model to assess effects of Ibudilast on fertilization; and (4) optimise high performance liquid chromatography (HPLC) techniques for routine detection of cyclic nucleotides in sperm cells. A two phase drug screening approach was used to systematically and comprehensively screen series of compounds in order to identify those that have clinically relevant enhancement of human sperm motility. In phase 1, 6 compounds (out of 43 compounds) were found to have strong effects on poor motility samples, with magnitude of response ≥60% increase in percentage total motility. Additionally, these compounds significantly enhanced sperm penetration into cervical mucus substitute (p≤0.05), and they did not affect sperm acrosomal integrity nor cause externalisation of phosphatidylserine (p=0.6 respectively). 63% of IVF samples treated with compounds #26, #37 and #38 had significant increase in percentage total motility. For ICSI samples, compounds #26, #37 and #38 were the most effective. In respect to total motility, 88%, 81% and 79% of samples treated with these compounds showed significant increases in total motility, and 94%, 93% and 81% of samples showed significant increases in percentage of progressive cells, respectively. Analysis of the signalling pathways, using PKA, sGC and PKG inhibitors, showed that chosen PDE inhibitors were working predominantly through PKA signalling pathways. Additionally, this study revealed that this pathway is needed for the maintenance of basal progressive motility and hyperactivation in human sperm. Animal IVF studies showed that addition of Ibudilast (compound #26) during sperm-oocyte incubation leads to higher IVF rates. Lastly, this study used an HPLC system to detect cAMP in boar sperm. This was done to explore if HPLC system can be used for high throughput detection of cyclic nucleotides in mammalian sperm.
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The effects of phosphodiesterase inhibitors on rat mast cells.January 2005 (has links)
Kam Man Fai Afia. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves [195]-224). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.v / Publications --- p.vi / Abbreviations --- p.vii / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- The Mast Cell --- p.2 / Chapter 1.1.1 --- Historical Perspective --- p.2 / Chapter 1.1.2 --- Mast Cell Origin and Development --- p.3 / Chapter 1.1.3 --- Mast Cell Heterogeneity --- p.5 / Chapter 1.1.3.1 --- Rodent Mast Cell Heterogeneity --- p.5 / Chapter 1.1.3.2 --- Human Mast Cell Heterogeneity --- p.7 / Chapter 1.1.4 --- Mast Cell Mediators --- p.10 / Chapter 1.1.4.1 --- Preformed Mediators --- p.11 / Chapter 1.1.4.2 --- Newly Synthesized Lipid Mediators --- p.14 / Chapter 1.1.4.3 --- Cytokines --- p.16 / Chapter 1.1.5 --- Mast Cell Activation --- p.17 / Chapter 1.1.5.1 --- Immunological Activation --- p.19 / Chapter 1.1.5.1.1 --- FcεIR Activation and Protein Tyrosine Phosphorylation --- p.19 / Chapter 1.1.5.1.2 --- Activation of Phospholipases --- p.20 / Chapter 1.1.5.1.3 --- The Role of Calcium --- p.22 / Chapter 1.1.5.1.3.1 --- Intracellular Calcium Mobilization --- p.23 / Chapter 1.1.5.1.3.2 --- Calcium Influx --- p.24 / Chapter 1.1.5.1.3.3 --- Mechanisms of Action of Calcium in Mast Cells --- p.28 / Chapter 1.1.5.1.4 --- The Role of G-proteins --- p.30 / Chapter 1.1.5.1.5. --- The Role of Cylic AMP --- p.33 / Chapter 1.1.5.1.2.1 --- Mechanisms of Action of Cyclic AMP in Mast Cells --- p.36 / Chapter 1.1.5.1.2.2 --- Implications for the Inhibitory Role of Cyclic AMP in Mast Cell Activation --- p.37 / Chapter 1.2 --- The Cyclic Nucleotide Phosphodiesterases --- p.39 / Chapter 1.2.1 --- Introduction --- p.39 / Chapter 1.2.2 --- Classification and Structure --- p.41 / Chapter 1.2.3 --- Distribution and Physiological Functions of the Different PDE Families --- p.45 / Chapter 1.2.4 --- Phosphodiesterase Inhibitors --- p.49 / Chapter 1.2.4.1 --- Non-selective PDE Inhibitors --- p.50 / Chapter 1.2.4.2 --- Selective PDE Inhibitors --- p.52 / Chapter 1.2.4.2.1 --- PDE1 and PDE2 Inhibitors --- p.52 / Chapter 1.2.4.2.2 --- PDE3 Inhibitors --- p.53 / Chapter 1.2.4.2.3 --- PDE4 Inhibitors --- p.54 / Chapter 1.2.4.2.4.1 --- PDE5 Inhibitors --- p.56 / Chapter 2. --- Materials and Methods --- p.59 / Chapter 2.1 --- Materials --- p.60 / Chapter 2.1.1 --- Drugs --- p.60 / Chapter 2.1.1.1 --- Phosphodiesterase Inhibitors --- p.60 / Chapter 2.1.1.2 --- Mast Cell Secretagogues --- p.61 / Chapter 2.1.2 --- Materials for Rat Peritoneal Mast Cell Experiments --- p.61 / Chapter 2.1.2.1 --- Materials for Rat Sensitization --- p.61 / Chapter 2.1.2.2 --- Materials for Buffers --- p.62 / Chapter 2.1.2.3 --- Materials for Histamine Assay --- p.62 / Chapter 2.1.2.4 --- Miscellaneous --- p.63 / Chapter 2.1.3 --- Materials for RBL-2H3 Cell Line Experiments --- p.63 / Chapter 2.1.3.1 --- Materials for Cell Culture --- p.63 / Chapter 2.1.3.2 --- Materials for Cell Sensitization and Enzyme Release --- p.64 / Chapter 2.1.3.3 --- Materials for β-Hexosaminidase Assay --- p.64 / Chapter 2.1.3.4 --- Miscellaneous --- p.64 / Chapter 2.2 --- Rat Peritoneal Mast Cell Experiments --- p.65 / Chapter 2.2.1 --- Preparation of Buffers --- p.65 / Chapter 2.2.2 --- Preparation of Stock Solutions --- p.66 / Chapter 2.2.2.1 --- Mast Cell Secretagogue Stock Solutions --- p.66 / Chapter 2.2.2.2 --- Phosphodiesterase Inhibitor Stock Solutions --- p.66 / Chapter 2.2.3 --- Animals and Cell Isolation --- p.71 / Chapter 2.2.3.1 --- Animals --- p.71 / Chapter 2.2.3.2 --- Sensitization of Animals --- p.71 / Chapter 2.2.3.3 --- Cell Isolation --- p.71 / Chapter 2.2.3.4 --- Cell Purification --- p.72 / Chapter 2.2.3.5 --- Determination of Cell Number and Viability --- p.73 / Chapter 2.2.4 --- General Protocol for Histamine Release and Histamine Measurement --- p.75 / Chapter 2.2.4.1 --- Histamine Release --- p.75 / Chapter 2.2.4.2 --- Spectrofluorometric Determination of Histamine Content --- p.76 / Chapter 2.2.4.2.1 --- Manual Histamine Assay --- p.76 / Chapter 2.2.4.2.2 --- Automated Histamine Assay --- p.78 / Chapter 2.2.4.3 --- Calculation of Histamine Levels --- p.78 / Chapter 2.2.4.4 --- Presentation and Statistics --- p.79 / Chapter 2.3 --- RBL-2H3 Cell Line Experiments --- p.80 / Chapter 2.3.1 --- Preparation of Stock Solutions --- p.80 / Chapter 2.3.2 --- Preparation of Materials for Enzyme Release and Assay --- p.81 / Chapter 2.3.2.1 --- Cell Culture --- p.81 / Chapter 2.3.2.2 --- Preparation of Cells for β-Hexosaminidase Release Experiments --- p.82 / Chapter 2.3.2.3 --- β-Hexosaminidase Release --- p.82 / Chapter 2.3.2.4 --- β-Hexosaminidase Assay --- p.83 / Chapter 3. --- Effects of Phosphodiesterase Inhibitors on Mediator Release from Rat Mast Cells --- p.84 / Chapter 3.1 --- Introduction --- p.85 / Chapter 3.2 --- Materials and Methods --- p.87 / Chapter 3.2.1 --- Rat Peritoneal Mast Cells --- p.87 / Chapter 3.2.1.1 --- Experiments Employing Immunological Stimulus in RPMCs --- p.87 / Chapter 3.2.1.2 --- Experiments Employing Non-Immunological Stimuli in RPMCs --- p.88 / Chapter 3.2.2 --- Rat Basophilic Leukemia Cells --- p.88 / Chapter 3.3 --- Results --- p.89 / Chapter 3.3.1 --- Rat Peritoneal Mast Cells --- p.89 / Chapter 3.3.1.1 --- Immunologically Activated Rat Peritoneal Mast Cells --- p.89 / Chapter 3.3.1.1.1 --- Effects of Non-Selective PDE Inhibitors on Anti-IgE-Mediated Histamine Release from RPMCs --- p.89 / Chapter 3.3.1.1.2 --- Effects of Selective PDE1 and PDE2 Inhibitors on Anti-IgE- Mediated Histamine Release from RPMCs --- p.90 / Chapter 3.3.1.1.3 --- Effects of Selective PDE3 Inhibitors on Anti-IgE-Mediated Histamine Release from RPMCs --- p.90 / Chapter 3.3.1.1.4 --- Effects of Selective PDE4 Inhibitors on Anti-IgE-Mediated Histamine Release from RPMCs --- p.91 / Chapter 3.3.1.1.5 --- Effects of Selective PDE5 Inhibitors on Anti-IgE-Mediated Histamine Release from RPMCs --- p.91 / Chapter 3.3.1.2 --- Non-Immunologically Activated Rat Peritoneal Mast Cells --- p.92 / Chapter 3.3.1.2.1 --- Effects of Selective PDE Inhibitors on Compound 48/80- Mediated Histamine Release from RPMCs --- p.92 / Chapter 3.3.1.2.2 --- Effects of Selective PDE Inhibitors on Histamine Release from RPMCs Stimulated by Calcium Ionophores --- p.93 / Chapter 3.3.2 --- Rat Basophilic Leukemia Cells --- p.93 / Chapter 3.3.2.1 --- Effects of Non-Selective PDE Inhibitors on Antigen-Mediated β-Hexosaminidase Release from RBL-2H3 Cells --- p.93 / Chapter 3.3.2.2 --- Effects of Selective PDE Inhibitors on Antigen-Mediated β-Hexosaminidase Release from RBL-2H3 Cells --- p.94 / Chapter 3.4 --- Discussion --- p.95 / Chapter 3.4.1 --- Rat Peritoneal Mast Cells --- p.95 / Chapter 3.4.1.1 --- Immunologically Activated RPMCs --- p.95 / Chapter 3.4.1.2 --- Non-Immunologically Activated RPMCs --- p.99 / Chapter 3.4.2 --- Rat Basophilic Leukemia Cells --- p.103 / Chapter 4. --- Combined Effects of Selective Phosphodiesterase Inhibitors on Immunologically Induced Histamine from Rat Mast Cells --- p.143 / Chapter 4.1 --- Introduction --- p.144 / Chapter 4.2 --- Materials and Methods --- p.144 / Chapter 4.2.1 --- Simultaneous Addition of PDE3 and PDE4 Inhibitors --- p.145 / Chapter 4.2.2 --- Sequential Addition of PDE3 and PDE4 Inhibitors --- p.145 / Chapter 4.3 --- Results --- p.146 / Chapter 4.3.1 --- Effects of the Selective Inhibitors for PDE3 and PDE4 Alone: Calculation of the Expected Inhibition Curve --- p.146 / Chapter 4.3.2 --- Effects of the Simultaneous Addition of PDE3 and PDE4 Inhibitors on Anti-IgE-Mediated Histamine Release from RPMCs --- p.148 / Chapter 4.3.2.1 --- Rolipram and Siguazodan --- p.148 / Chapter 4.3.2.2 --- Ro 20-1724 and Siguazodan --- p.149 / Chapter 4.3.2.3 --- Rolipram and Quazinone --- p.149 / Chapter 4.3.2.4 --- Ro 20-1724 and Quazinone --- p.150 / Chapter 4.3.3 --- Effects of the Sequential Addition of PDE3 and PDE4 Inhibitors on Anti-IgE-Mediated Histamine Release from RPMCs --- p.150 / Chapter 4.3.3.1 --- Rolipram and Siguazodan --- p.150 / Chapter 4.3.3.2 --- Ro 20-1724 and Siguazodan --- p.151 / Chapter 4.3.3.3 --- Rolipram and Quazinone --- p.151 / Chapter 4.3.3.4 --- Ro 20-1724 and Quazinone --- p.152 / Chapter 4.4 --- Discussion --- p.153 / Chapter 5. --- Future Directions --- p.191 / Chapter 5.1 --- Future Directions --- p.192 / References --- p.195
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