Essential hypertension (EH) is a risk factor for many cardiovascular disorders. Treatment of established EH, especially for prolonged control of this pathogenic process, represents a great challenge. Moreover, hypertension is considered an important risk factor for the development of many other diseases, e.g. erectile dysfunction. <p> Hemin and other heme derivatives, e.g. heme-L-lysinate (HLL) and heme-L-arginate, have been used extensively to upregulate expression of heme oxygenase (HO) and production of endogenous carbon monoxide (CO). Short-term hemin administration for 4-5 days has been shown to markedly decrease high blood pressure (BP) in spontaneously hypertensive rats (SHR), but not in normotensive Wistar-Kyoto (WKY) or Sprague Dawley (SD) rats. This short-term therapy was effective in treating young, but not adult SHR. In the present study, hemin (15 mg/kg/day) was administered to 12-week old adult SHR through subcutaneously implanted osmotic minipumps for 3 consecutive weeks (the hemin protocol). Into the second week of the hemin protocol, BP of SHR was normalized from 203.2 ± 2.5 to 123.4 ±1.9 mmHg (n=20, p<0.001). There was no further decrease of BP in the remaining days of the hemin protocol. Normalization of BP in these treated SHR was maintained for 9 months after the removal of hemin pumps. <p>To further investigate the metabolic characteristics of hemin during hemin protocol administration, we attempted to monitor circulatory heme levels. A valid standard calibration curve was established using hemin or HLL in <i>in vitro</i> experiments. It was established that the basal serum level of heme was negligible in all rat strains prior to hemin protocol initiation. During the hemin protocol, serum heme level of all rats was significantly elevated; however, it quickly dropped to basal levels thereafter. <p>At the end of the 3-week hemin protocol, HO-1 expression, HO activity, soluble guanylyl cyclase (sGC) expression, and cyclic guanosine monophosphate (cGMP) content were all increased, but phosphodiesterase-5 (PDE-5) expression was down-regulated in the mesenteric arteries. The hemin protocol also reversed SHRs decreased arterial lumen size, and increased expression levels of vascular endothelial growth factor. These changes lasted 9 months after the hemin protocol. The hemin protocol did not cause hepatic or renal toxicity. Our study thus unmasks a novel hemin protocol that will not only normalize BP in SHR with established hypertension but, more importantly, also provide long-lasting anti-hypertension protection. Sustained upregulation of the HO-regulated signaling pathways and reversal of vascular remodeling in small peripheral vessels in treated SHR are among potential underlying mechanisms for the anti-hypertensive effect of the hemin protocol.<p>We further studied if the beneficial effects of hemin protocol on BP of SHR could be extended to improvement of their penile erection. Intracavernosal pressure changes after electrical stimulation of the cavernous nerve (CN) were monitored in adult SHR and age-matched normotensive SD rats after administration of either hemin or hydralazine. Expression levels of HO-1, HO-2, sGC, and PDE-5 in penile tissues were also examined. Frequency-dependent intracavernosal pressure (ICP) changes were reduced in adult SHR. Three weeks after hemin treatment, ICP responses to CN stimulations were significantly increased to the level of normotensive rats, which was linked to normalization of BP of hemin-treated SHR. Hydralazine-treated SHR experienced normalization of BP but not ICP after 3 weeks of treatment. Expression of HO-1 and sGC was upregulated and that of PDE-5 downregulated in hemin-treated SHR. Decreased ICP response in adult SHR can be improved through chronic hemin treatment of SHR. Prolonged upregulation of HO-1 and sGC as well as lowered expression of PDE-5 may account for normalization of erectile dysfunction in SHR subsequent to hemin treatment. <p>This thesis reports for the first time that 21-day hemin administration led to a 9-month normalization of high BP of adult SHR. These effects were mediated through sustained stimulation of the HO/CO system and its downstream effectors targets. Increased activity of HO-1 led to normalization of the abnormally high expression level of VEGF in peripheral mesenteric arteries of adult SHR. Subsequently, this resulted in reversal of the eutrophic remodeling of these arteries, which seems to be the priniciple determinant of the long-term normalization of BP observed for 9 months after stoppage of hemin treatment. The invention of hemin protocol offers a new therapeutic approach for the clinical management of established hypertension for a long duration.<p>Our study, for the first time, correlated changes in serum heme levels with BP levels after injection of hemin or HLL in normotensive and hypertensive rats. Application of this heme monitoring technology will also pave the way for clinical application of hemin therapy in treatment of EH.<p> Another intriguing finding in this thesis is that upregulation of HO-1, through the hemin protocol, led to improvement of abnormally low ICP encountered in adult SHR. Upregulation of HO-1 may represent a novel therapeutic approach to treat hypertension-related erectile dysfunction.

Essential hypertension (EH) is a risk factor for many cardiovascular disorders. Treatment of established EH, especially for prolonged control of this pathogenic process, represents a great challenge. Moreover, hypertension is considered an important risk factor for the development of many other diseases, e.g. erectile dysfunction. <p> Hemin and other heme derivatives, e.g. heme-L-lysinate (HLL) and heme-L-arginate, have been used extensively to upregulate expression of heme oxygenase (HO) and production of endogenous carbon monoxide (CO). Short-term hemin administration for 4-5 days has been shown to markedly decrease high blood pressure (BP) in spontaneously hypertensive rats (SHR), but not in normotensive Wistar-Kyoto (WKY) or Sprague Dawley (SD) rats. This short-term therapy was effective in treating young, but not adult SHR. In the present study, hemin (15 mg/kg/day) was administered to 12-week old adult SHR through subcutaneously implanted osmotic minipumps for 3 consecutive weeks (the hemin protocol). Into the second week of the hemin protocol, BP of SHR was normalized from 203.2 ± 2.5 to 123.4 ±1.9 mmHg (n=20, p<0.001). There was no further decrease of BP in the remaining days of the hemin protocol. Normalization of BP in these treated SHR was maintained for 9 months after the removal of hemin pumps. <p>To further investigate the metabolic characteristics of hemin during hemin protocol administration, we attempted to monitor circulatory heme levels. A valid standard calibration curve was established using hemin or HLL in <i>in vitro</i> experiments. It was established that the basal serum level of heme was negligible in all rat strains prior to hemin protocol initiation. During the hemin protocol, serum heme level of all rats was significantly elevated; however, it quickly dropped to basal levels thereafter. <p>At the end of the 3-week hemin protocol, HO-1 expression, HO activity, soluble guanylyl cyclase (sGC) expression, and cyclic guanosine monophosphate (cGMP) content were all increased, but phosphodiesterase-5 (PDE-5) expression was down-regulated in the mesenteric arteries. The hemin protocol also reversed SHRs decreased arterial lumen size, and increased expression levels of vascular endothelial growth factor. These changes lasted 9 months after the hemin protocol. The hemin protocol did not cause hepatic or renal toxicity. Our study thus unmasks a novel hemin protocol that will not only normalize BP in SHR with established hypertension but, more importantly, also provide long-lasting anti-hypertension protection. Sustained upregulation of the HO-regulated signaling pathways and reversal of vascular remodeling in small peripheral vessels in treated SHR are among potential underlying mechanisms for the anti-hypertensive effect of the hemin protocol.<p>We further studied if the beneficial effects of hemin protocol on BP of SHR could be extended to improvement of their penile erection. Intracavernosal pressure changes after electrical stimulation of the cavernous nerve (CN) were monitored in adult SHR and age-matched normotensive SD rats after administration of either hemin or hydralazine. Expression levels of HO-1, HO-2, sGC, and PDE-5 in penile tissues were also examined. Frequency-dependent intracavernosal pressure (ICP) changes were reduced in adult SHR. Three weeks after hemin treatment, ICP responses to CN stimulations were significantly increased to the level of normotensive rats, which was linked to normalization of BP of hemin-treated SHR. Hydralazine-treated SHR experienced normalization of BP but not ICP after 3 weeks of treatment. Expression of HO-1 and sGC was upregulated and that of PDE-5 downregulated in hemin-treated SHR. Decreased ICP response in adult SHR can be improved through chronic hemin treatment of SHR. Prolonged upregulation of HO-1 and sGC as well as lowered expression of PDE-5 may account for normalization of erectile dysfunction in SHR subsequent to hemin treatment. <p>This thesis reports for the first time that 21-day hemin administration led to a 9-month normalization of high BP of adult SHR. These effects were mediated through sustained stimulation of the HO/CO system and its downstream effectors targets. Increased activity of HO-1 led to normalization of the abnormally high expression level of VEGF in peripheral mesenteric arteries of adult SHR. Subsequently, this resulted in reversal of the eutrophic remodeling of these arteries, which seems to be the priniciple determinant of the long-term normalization of BP observed for 9 months after stoppage of hemin treatment. The invention of hemin protocol offers a new therapeutic approach for the clinical management of established hypertension for a long duration.<p>Our study, for the first time, correlated changes in serum heme levels with BP levels after injection of hemin or HLL in normotensive and hypertensive rats. Application of this heme monitoring technology will also pave the way for clinical application of hemin therapy in treatment of EH.<p> Another intriguing finding in this thesis is that upregulation of HO-1, through the hemin protocol, led to improvement of abnormally low ICP encountered in adult SHR. Upregulation of HO-1 may represent a novel therapeutic approach to treat hypertension-related erectile dysfunction.

Thesis (M.S.)--Uniformed Services University of the Health Sciences, 2002 / Typescript (photocopy)

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 Pena_ClesioBorges_M.pdf: 779579 bytes, checksum: aeca20777087c88ff1ca05b3acc4316c (MD5) 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

A moxidectina (MOX) é um antiparasitário utilizado na clínica veterinária. Em mamíferos seu mecanismo de ação envolve o ácido ?-aminobutírico (GABA), um neurotransmissor que tem papel relevante na regulação dos comportamentos sexual e motor. Dados anteriores por nós obtidos mostraram que a MOX prejudicou o comportamento sexual e a coordenação motora de ratos machos avaliados na trave elevada. Assim, dando continuidade a esse estudo, o objetivo deste trabalho foi avaliar os efeitos da administração da dose terapêutica de MOX (0,2 mg/kg) na motivação sexual e ereção peniana de ratos machos, bem como estudar seu envolvimento em diferentes sistemas de neurotransmissão central. Em todos os experimentos os ratos do grupo experimental receberam a MOX por via subcutânea (SC); e os ratos do grupo controle receberam 1 ml/kg de óleo de amêndoas pela mesma via, e foram avaliados após 72 h. A motivação sexual foi avaliada em um aparelho constituído de uma arena e dois compartimentos separados desta por tela de arame; num compartimento foi colocado um rato macho experiente e no outro uma fêmea sexualmente receptiva. Neste aparelho foi medido o tempo que o rato permaneceu nas proximidades de cada compartimento. Os resultados obtidos neste experimento não mostraram diferenças significantes entre os grupos. A ereção peniana foi induzida pela administração SC de 80 ?g/kg de apomorfina, sendo avaliadas a latência e a freqüência de ereção. Os resultados mostraram aumento da latência e redução da freqüência de ereção peniana dos animais tratados com MOX, enquanto que a administração dos antagonistas GABAérgicos (biculina e faclofen) não alterou estes parâmetros. Por outro lado, observou-se que a biculina (antagonista GABAA) reverteu os efeitos da MOX na ereção peniana, enquanto o faclofen aumentou a freqüência de ereção peniana em ratos tratados com a MOX. Quanto aos níveis hipotalâmicos e estriatais de neurotransmissores e metabólitos, observou-se que a MOX reduziu os níveis estriatais de dopamina e de seu metabólito ácido homovanílico (HVA) e também os níveis hipotalâmicos de GABA. Estes dados sugerem que a MOX embora não interfira na motivação sexual, prejudica o desempenho sexual avaliado pela ereção peniana. Esse efeito da MOX pode ser atribuído a sua ação em receptores GABAA, os quais modulam receptores tipo B, aumentando a liberação de GABA, e 72 h depois, conseqüente redução dos níveis deste neurotransmissor no hipotálamo (uma das áreas centrais envolvidas com o comportamento sexual) e também dos níveis de dopamina e seu metabólito HVA no estriado, área do sistema nervoso central relacionada com a função motora e na qual neurônios GABAérgicos modulam a atividade de neurônios dopaminérgicos. / The moxidectina (MOX) is an antiparasitic drug used in veterinary clinic. In mammals its mechanism of action involves GABA, neurotransmitter that has an important role in the regulation of the sexual and motor behaviors. Previous data showed that MOX impair male rat\'s sexual behavior and motor coordination observed at wooden dowel. The objective of the present work was to evaluate the effects of therapeutic dose of MOX (0.2 mg/kg) in sexual motivation and penile erection of male rats, as well as to study its involvement in different central systems of neurotransmission. In all experiments the rats of experimental groups received MOX subcutaneous (SC), and the rats of control groups received 1.0 mL/kg of almonds oil (SC), and were observed after 72h. Sexual motivation test was performed in an arena with two cages, separate from the arena with a wall of wire screen; in one cage was put an intact male rat and in the other one, a sexually receptive female. In this test was measured the time that the rats stayed near of each cage. The data obtained in this experiment didn\'t show any significant differences among the groups. The penile erection (PE) was induced by 80 ?g/kg of Apomorphine (SC), being evaluated the latency to and frequency of PE. The results showed increased latency and reduction of the frequency of PE of animals treated with MOX, while the GABAergic antagonists\' administration (Biculline and Phaclofen) didn\'t change these parameters. On the other hand, it was observed that the Biculline (GABAA antagonist) reversed the effects of MOX in PE, while the Phaclofen increased the frequency of PE in rats treated with MOX. About Hypothalamic and Striatal neurotransmitters levels and their metabolites, was observed that MOX reduced Dopamine (DA) and its metabolite homovanillic acid (HVA) striatal levels and hypothalamic GABA levels. These data suggest that MOX although doesn\'t interfere in sexual motivation, impair sexual performance evaluated by penile erection. This effect of MOX can be attributed to its action in GABAA receptors, which modulate type B receptors, increasing GABA release, and consequent reduction of its levels in the Hypothalamus (one of the central areas involved with sexual behavior) and also, reduction of the DA and its metabolite HVA striatal levels. Striatum is a central nervous system area related with motor function in which GABAergic neurons modulate the activity of dopaminergic neurons.

A moxidectina (MOX) é um antiparasitário utilizado na clínica veterinária. Em mamíferos seu mecanismo de ação envolve o ácido ?-aminobutírico (GABA), um neurotransmissor que tem papel relevante na regulação dos comportamentos sexual e motor. Dados anteriores por nós obtidos mostraram que a MOX prejudicou o comportamento sexual e a coordenação motora de ratos machos avaliados na trave elevada. Assim, dando continuidade a esse estudo, o objetivo deste trabalho foi avaliar os efeitos da administração da dose terapêutica de MOX (0,2 mg/kg) na motivação sexual e ereção peniana de ratos machos, bem como estudar seu envolvimento em diferentes sistemas de neurotransmissão central. Em todos os experimentos os ratos do grupo experimental receberam a MOX por via subcutânea (SC); e os ratos do grupo controle receberam 1 ml/kg de óleo de amêndoas pela mesma via, e foram avaliados após 72 h. A motivação sexual foi avaliada em um aparelho constituído de uma arena e dois compartimentos separados desta por tela de arame; num compartimento foi colocado um rato macho experiente e no outro uma fêmea sexualmente receptiva. Neste aparelho foi medido o tempo que o rato permaneceu nas proximidades de cada compartimento. Os resultados obtidos neste experimento não mostraram diferenças significantes entre os grupos. A ereção peniana foi induzida pela administração SC de 80 ?g/kg de apomorfina, sendo avaliadas a latência e a freqüência de ereção. Os resultados mostraram aumento da latência e redução da freqüência de ereção peniana dos animais tratados com MOX, enquanto que a administração dos antagonistas GABAérgicos (biculina e faclofen) não alterou estes parâmetros. Por outro lado, observou-se que a biculina (antagonista GABAA) reverteu os efeitos da MOX na ereção peniana, enquanto o faclofen aumentou a freqüência de ereção peniana em ratos tratados com a MOX. Quanto aos níveis hipotalâmicos e estriatais de neurotransmissores e metabólitos, observou-se que a MOX reduziu os níveis estriatais de dopamina e de seu metabólito ácido homovanílico (HVA) e também os níveis hipotalâmicos de GABA. Estes dados sugerem que a MOX embora não interfira na motivação sexual, prejudica o desempenho sexual avaliado pela ereção peniana. Esse efeito da MOX pode ser atribuído a sua ação em receptores GABAA, os quais modulam receptores tipo B, aumentando a liberação de GABA, e 72 h depois, conseqüente redução dos níveis deste neurotransmissor no hipotálamo (uma das áreas centrais envolvidas com o comportamento sexual) e também dos níveis de dopamina e seu metabólito HVA no estriado, área do sistema nervoso central relacionada com a função motora e na qual neurônios GABAérgicos modulam a atividade de neurônios dopaminérgicos. / The moxidectina (MOX) is an antiparasitic drug used in veterinary clinic. In mammals its mechanism of action involves GABA, neurotransmitter that has an important role in the regulation of the sexual and motor behaviors. Previous data showed that MOX impair male rat\'s sexual behavior and motor coordination observed at wooden dowel. The objective of the present work was to evaluate the effects of therapeutic dose of MOX (0.2 mg/kg) in sexual motivation and penile erection of male rats, as well as to study its involvement in different central systems of neurotransmission. In all experiments the rats of experimental groups received MOX subcutaneous (SC), and the rats of control groups received 1.0 mL/kg of almonds oil (SC), and were observed after 72h. Sexual motivation test was performed in an arena with two cages, separate from the arena with a wall of wire screen; in one cage was put an intact male rat and in the other one, a sexually receptive female. In this test was measured the time that the rats stayed near of each cage. The data obtained in this experiment didn\'t show any significant differences among the groups. The penile erection (PE) was induced by 80 ?g/kg of Apomorphine (SC), being evaluated the latency to and frequency of PE. The results showed increased latency and reduction of the frequency of PE of animals treated with MOX, while the GABAergic antagonists\' administration (Biculline and Phaclofen) didn\'t change these parameters. On the other hand, it was observed that the Biculline (GABAA antagonist) reversed the effects of MOX in PE, while the Phaclofen increased the frequency of PE in rats treated with MOX. About Hypothalamic and Striatal neurotransmitters levels and their metabolites, was observed that MOX reduced Dopamine (DA) and its metabolite homovanillic acid (HVA) striatal levels and hypothalamic GABA levels. These data suggest that MOX although doesn\'t interfere in sexual motivation, impair sexual performance evaluated by penile erection. This effect of MOX can be attributed to its action in GABAA receptors, which modulate type B receptors, increasing GABA release, and consequent reduction of its levels in the Hypothalamus (one of the central areas involved with sexual behavior) and also, reduction of the DA and its metabolite HVA striatal levels. Striatum is a central nervous system area related with motor function in which GABAergic neurons modulate the activity of dopaminergic neurons.

INTRODUÇÃO: O aracnídeo Phoneutria nigriventer, também conhecido por aranha-armadeira, possui um veneno complexo, contendo vários peptídeos que ativam canais iônicos nas células. Dentre estes, só dois neuropeptídeos, Tx2-5 e Tx2-6, destacam-se por relaxar o músculo liso trabecular do corpo cavernoso, induzindo ereção peniana em camundongos e ratos. Este efeito tem sido associado à produção de oxido nítrico pela ativação de óxido nítrico sintases. No entanto, faltam estudos mais amplos para determinar o papel de Tx2-6 na indução da ereção. OBJETIVOS: Identificar os genes diferencialmente expressos no tecido erétil de camundongos após indução da ereção pela Tx2-6 utilizando microarranjos de oligonucleotídeos. Validação dos resultados obtidos nos microarranjos por PCR quantitativa e imuno-histoquímica. MATERIAIS E MÉTODOS: Camundongos machos e adultos da linhagem Swiss foram divididos em dois grupos: controle (n=10), inoculados pela via intracavernosa com 20 l de solução salina; e tratado (n=10), os quais receberam 0,006gg/animal do peptídeo Tx2-6 diluído em 20 l de salina pela via intracavernosa. Uma hora após o início da ereção no grupo tratado todos os animais foram sacrificados e retirou-se o pênis. Este último foi dividido em dois fragmentos, uma parte do material foi congelada em nitrogênio líquido e mantida a 80°C até a extração do RNA para os experimentos de microarranjos e PCR quantitativa; outra parte foi utilizada para avaliação imuno-histoquímica. RESULTADOS: No grupo tratado a ereção foi observada 30-45 minutos após aplicação de Tx2-6 e mantida durante 120 minutos. Os camundongos de grupo controle não apresentaram nenhum indício de ereção. Nos experimentos de microarranjos, onde foram analisados 34.000 genes representando o genoma total do camundongo, identificou-se 3.803 (12,3%) genes com expressão diferencial de pelo menos ±1,5 vez entre os grupos (1.823 genes superexpressos e 1.980 genes subexpressos no grupo tratado comparado ao controle). Os genes ednrb, sparc, fn1, sstr2, pdgfr foram selecionados para validação dos microarranjos por PCR quantitativa e confirmaram a superexpressão em relação aos controles. As proteínas Fn1, Sstr2 e Pdgfr resultaram aumentadas no grupo tratado após avaliação imuno-histoquímica. CONCLUSÕES: A inoculação de Tx2-6 pela via intracavernosa alterou o perfil de expressão gênica no tecido erétil de camundongos. O número de genes superexpressos foi similar ao de genes subexpressos. Serão necessários outros estudos para entender melhor as vias moleculares que Tx2-6 afeta na indução da ereção peniana. / INTRODUCTION: The Phoneutria nigriventer arachnid, also known as armed-spider, has a complex venom, composed by several peptides that affect cellular ionic channels. Among these, only two neuropeptides, Tx2-5 and Tx2-6 induce penile erection in mice and rats and this effect has been associated with the production of nitric oxide by the activation of nitric oxide synthases. Moreover, there is a scarcity of studies focusing on the role of Tx2-6 in the induction of erection. OBJECTIVES: To identify the differently expressed genes in the erectile tissue of mice after erection induction by Tx2-6 using oligonucleotide microarrays. To validate microarray results by quantitative PCR and immunohistochemistry. MATERIALS AND METHODS: Swiss adult male mice were divided in two groups: control (n=10) were injected intracavernously with 20 gl of saline solution; and treated (n=10) were injected intracavernously with 0.006gg/mouse of the Tx2-6 peptide diluted in 20 gl of saline solution. After checking the penile erection in the treated group, all mice were sacrificed one hour after the beginning of erection for the removal of the penis. Penile organ was divided into two fragments, one piece was immediately frozen in liquid-nitrogen and stored at -80°C until RNA extraction to make the microarray and quantitative PCR experiments; the other was reserved for immunohistochemistry analysis. RESULTS: In the treated group, erection was noticed 30-45 minutes after Tx2-6 inoculation and lasted for 120 minutes. Control mice did not present any sign of erection. Considering as differentially expressed genes with a ±1.5 fold expression difference, of the 34,000 genes on the microarray we identified 3,803 (12.3%) genes differentially expressed between the groups (1,823 genes up-regulated and 1,980 genes down-regulated in the treated group compared to controls). The ednrb, sparc, fn1, sstr2, pdgfr genes were selected for validation of microarray results by using quantitative PCR and confirmed the up-regulation when compared to controls. After immunohistochemistry analysis the Fn1, Sstr2 and Pdgfr proteins were found increased in the treated group. CONCLUSIONS: The intracavernous inoculation of Tx2-6 modified the gene expression profile of erectile tissue of mice. The number of upregulated and down-regulated genes was similar. Further studies are needed to understand the molecular pathways that Tx2-6 affect to induce penile erection.

INTRODUÇÃO: O aracnídeo Phoneutria nigriventer, também conhecido por aranha-armadeira, possui um veneno complexo, contendo vários peptídeos que ativam canais iônicos nas células. Dentre estes, só dois neuropeptídeos, Tx2-5 e Tx2-6, destacam-se por relaxar o músculo liso trabecular do corpo cavernoso, induzindo ereção peniana em camundongos e ratos. Este efeito tem sido associado à produção de oxido nítrico pela ativação de óxido nítrico sintases. No entanto, faltam estudos mais amplos para determinar o papel de Tx2-6 na indução da ereção. OBJETIVOS: Identificar os genes diferencialmente expressos no tecido erétil de camundongos após indução da ereção pela Tx2-6 utilizando microarranjos de oligonucleotídeos. Validação dos resultados obtidos nos microarranjos por PCR quantitativa e imuno-histoquímica. MATERIAIS E MÉTODOS: Camundongos machos e adultos da linhagem Swiss foram divididos em dois grupos: controle (n=10), inoculados pela via intracavernosa com 20 l de solução salina; e tratado (n=10), os quais receberam 0,006gg/animal do peptídeo Tx2-6 diluído em 20 l de salina pela via intracavernosa. Uma hora após o início da ereção no grupo tratado todos os animais foram sacrificados e retirou-se o pênis. Este último foi dividido em dois fragmentos, uma parte do material foi congelada em nitrogênio líquido e mantida a 80°C até a extração do RNA para os experimentos de microarranjos e PCR quantitativa; outra parte foi utilizada para avaliação imuno-histoquímica. RESULTADOS: No grupo tratado a ereção foi observada 30-45 minutos após aplicação de Tx2-6 e mantida durante 120 minutos. Os camundongos de grupo controle não apresentaram nenhum indício de ereção. Nos experimentos de microarranjos, onde foram analisados 34.000 genes representando o genoma total do camundongo, identificou-se 3.803 (12,3%) genes com expressão diferencial de pelo menos ±1,5 vez entre os grupos (1.823 genes superexpressos e 1.980 genes subexpressos no grupo tratado comparado ao controle). Os genes ednrb, sparc, fn1, sstr2, pdgfr foram selecionados para validação dos microarranjos por PCR quantitativa e confirmaram a superexpressão em relação aos controles. As proteínas Fn1, Sstr2 e Pdgfr resultaram aumentadas no grupo tratado após avaliação imuno-histoquímica. CONCLUSÕES: A inoculação de Tx2-6 pela via intracavernosa alterou o perfil de expressão gênica no tecido erétil de camundongos. O número de genes superexpressos foi similar ao de genes subexpressos. Serão necessários outros estudos para entender melhor as vias moleculares que Tx2-6 afeta na indução da ereção peniana. / INTRODUCTION: The Phoneutria nigriventer arachnid, also known as armed-spider, has a complex venom, composed by several peptides that affect cellular ionic channels. Among these, only two neuropeptides, Tx2-5 and Tx2-6 induce penile erection in mice and rats and this effect has been associated with the production of nitric oxide by the activation of nitric oxide synthases. Moreover, there is a scarcity of studies focusing on the role of Tx2-6 in the induction of erection. OBJECTIVES: To identify the differently expressed genes in the erectile tissue of mice after erection induction by Tx2-6 using oligonucleotide microarrays. To validate microarray results by quantitative PCR and immunohistochemistry. MATERIALS AND METHODS: Swiss adult male mice were divided in two groups: control (n=10) were injected intracavernously with 20 gl of saline solution; and treated (n=10) were injected intracavernously with 0.006gg/mouse of the Tx2-6 peptide diluted in 20 gl of saline solution. After checking the penile erection in the treated group, all mice were sacrificed one hour after the beginning of erection for the removal of the penis. Penile organ was divided into two fragments, one piece was immediately frozen in liquid-nitrogen and stored at -80°C until RNA extraction to make the microarray and quantitative PCR experiments; the other was reserved for immunohistochemistry analysis. RESULTS: In the treated group, erection was noticed 30-45 minutes after Tx2-6 inoculation and lasted for 120 minutes. Control mice did not present any sign of erection. Considering as differentially expressed genes with a ±1.5 fold expression difference, of the 34,000 genes on the microarray we identified 3,803 (12.3%) genes differentially expressed between the groups (1,823 genes up-regulated and 1,980 genes down-regulated in the treated group compared to controls). The ednrb, sparc, fn1, sstr2, pdgfr genes were selected for validation of microarray results by using quantitative PCR and confirmed the up-regulation when compared to controls. After immunohistochemistry analysis the Fn1, Sstr2 and Pdgfr proteins were found increased in the treated group. CONCLUSIONS: The intracavernous inoculation of Tx2-6 modified the gene expression profile of erectile tissue of mice. The number of upregulated and down-regulated genes was similar. Further studies are needed to understand the molecular pathways that Tx2-6 affect to induce penile erection.

Orientador: Gilberto de Nucci / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-26T11:10:20Z (GMT). No. of bitstreams: 1 Arruda_AndreMoreiraMartins_M.pdf: 11172054 bytes, checksum: db7fb87cc200cb091d3be4733e8d8af5 (MD5) Previous issue date: 2013 / Resumo: A presença de um par de órgãos copuladores, os hemipênis, é a característica mais singular do grupo Squamata, que reúne as serpentes e os lagartos. Para que ocorra a ereção, o hemipênis sofre ingurgitamento dos corpos cavernosos por sangue e linfa, além de contar com o auxílio da contração do músculo propulsor do pênis e o relaxamento do músculo retrator. O coito nestes animais pode durar até 28 horas, porém, os mecanismos envolvidos, as estruturas e sua base farmacológica de funcionamento são ainda pouco conhecidas. O hemipênis consiste de dois corpos cavernosos funcionalmente concêntricos, um deles contendo feixes de fibras musculares lisas. Em mamíferos, sintases de NO neuronais e endoteliais estão presentes em estruturas neurais e no endotélio, respectivamente, enquanto a guanilato ciclase solúvel e PDE5 (fosfodiesterase tipo 5) estão expressas no músculo liso trabecular. Partindo disto, para investigar as vias presentes no tecido das cobras, foram construídas curvas concentração-resposta cumulativas de relaxamento para a acetilcolina (ACh), nitroprussiato de sódio (SNP), BAY41-2272 e tadalafil em corpos cavernosos de Crotalus (CCC) pré-contraídos com fenilefrina. Relaxamentos induzidos por estímulo elétrico (EFS) também foram feitos na ausência e presença de L-NAME (100 mm), ODQ (10 mM) e tetrodotoxina (TTX, 1 mM). Em CCC pré-contraídos, o relaxamento dependente de frequência, gerado por EFS, durou três vezes mais do que aqueles em CC mamíferos. Embora estes relaxamentos sejam praticamente abolidos por L-NAME ou ODQ, eles não foram afetados pela TTX. Em contraste, o EFS promoveu relaxamento em corpos cavernosos de sagui que haviam sido incubados com TTX / Abstract: The presence of a pair of copulatory organs, the hemipenes, is the most unique feature of the group Squamata, which includes snakes and lizards. For an erection to occur, the hemipenes suffer engorgement of the corpora cavernosa with blood and lymph, besides counting with the aid of contraction of the propellant muscle and relaxation of penis retractor muscle. Coitus in these animals can last up to 28 hours, however, the mechanisms involved, the structures and their pharmacological basis are still little known. The hemipenis consists of two concentric functionally cavernous bodies, one containing bundles of smooth muscle fibers. In mammals, neuronal NO synthases and endothelial cells are present in the endothelium and neuronal structures, respectively, whereas the soluble guanylate cyclase and PDE5 (phosphodiesterase type 5) are expressed in trabecular smooth muscle. To investigas the tissue were constructed cumulative concentration-response curves for relaxation to acetylcholine (Ach), sodium nitroprusside (SNP), BAY41-2272 and tadalafil in the corpora cavernosa of Crotalus (CCC) pre contracted with phenylephrine. Relaxations induced by electrical stimulation (EFS) was also tested in the presence and absence of L-NAME (100 mm), ODQ (10 mM) and tetrodotoxin (TTX, 1 mM). In precontracted CCC, dependent relaxation frequency generated by EFS last three-times more than those in DC mammals. Although these relaxations are virtually abolished by L-NAME or ODQ, they were not affected by TTX. In contrast, EFS caused a relaxation of the corpus cavernosum in marmosets that had been incubated with TTX / Mestrado / Farmacologia / Mestra em Farmacologia