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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Imaging brain aromatase by using PET : A way to study anabolic steroid abuse

Takahashi, Kayo January 2008 (has links)
Aromatase is an enzyme that facilitates the conversion of androgens to estrogens and may play a role in mood and mental status. The main theme of this thesis is the imaging of brain aromatase by use of the PET technique. The PET tracer for aromatase, 11C-labeled vorozole (VOZ) was developed and evaluated by with in vitro and in vivo methods. In vitro experiments using rat brain showed that VOZ was distributed in the medial amygdala, bed nucleus of the stria terminalis and medial preoptic area, regions of the brain known to be rich in aromatase and the KD value was determined to be 0.60 nM. The in vivo PET study in rhesus monkey brain revealed that VOZ penetrated the blood-brain barrier and accumulated in the amygdala and hypothalamus. Taken together, VOZ is a good PET tracer for in vivo aromatase imaging with high affinity and high sensitivity. This technique was applied to an investigation of brain aromatase under the physiological conditions simulating anabolic-androgenic steroid abuse. A significant increase in VOZ binding by anabolic-androgenic steroids was observed in the bed nucleus of stria terminalis and medial preoptic area in the rat brain. In contrast, no significant change in binding was observed in the medial amygdala. These results indicate that the manner of regulation of aromatase expression might be different in the bed nucleus of stria terminalis and medial preoptic area compared with that in the medial amygdala. The aromatase expression was suggested to be regulated through androgen receptors, as indicated in a study with flutamide treatment. The increased aromatase expression was seen in neurons. The PET study with anabolic steroid-treated rhesus monkeys also showed increased VOZ binding in the hypothalamus but not in the amygdala. The alteration of density of aromatase binding in the hypothalamic area could explain some psychological features of anabolic-androgenic steroid abusers. Novel PET tracers for aromatase were developed and examined. The two newly synthesized 18F-labeled vorozole analogs, [18F]FVOZ and [18F]FVOO, displayed different characteristics. Both tracers showed similar binding pattern as VOZ; however, [18F]FVOO was metabolized very quickly, meaning that this tracer is not suitable as a PET tracer. On the other hand, [18F]FVOZ can be an appropriate PET tracer. The role of aromatase in the human brain has not been clarified yet. To approach this problem by in vivo methods, we have just started PET studies to explore aromatase expression in humans.
22

Activational effects of exogenous steroid hormones on cognitive performance: A study of anabolic-androgenic steroids in men

Mish, Sandra J. 01 May 2008 (has links)
Objective: Despite widespread drug testing in sports and warnings about the potential risks of using anabolic-androgenic steroids (AAS), non-medical use is prevalent among athletes, non-athletes, and disturbingly among adolescents. To date, most research has focused on the anabolic properties and short-term health risks of AAS use. In contrast, studies investigating the effects on cognitive function in men using high doses of multiple exogenous steroids are lacking. The primary purpose of this naturalistic study was to examine the effects of non-medical steroid use on sex-related cognitive abilities in male bodybuilders. The secondary purpose of the study was to evaluate the psychological functioning of male bodybuilders who use AASs. Methods: Eight male bodybuilders who used high doses of AASs were matched with bodybuilding and aerobic controls who had never used AASs, according to age, education, and estimated verbal intelligence. AAS use of the bodybuilders appeared similar to reports in the literature of self-administered AASs regimens used by strength athletes. All groups underwent a battery of cognitive tests and self-report psychological inventories, and had serum total testosterone and binding proteins measured immediately after testing. Cognitive measures selected were those that have previously shown sex differences. The study examined four psychological domains: aggression, personality, body image, and eating-disordered attitudes/behaviours. Results: Male bodybuilders who used AASs scored significantly lower than controls on mental rotations and on the WAIS-III Digit-Symbol Coding subtest. There were no other significant group differences on the cognitive tasks. A curvilinear (inverted U) relationship was identified between spatial ability and total testosterone in men who did not use AASs. As there were only a few AAS users in the current study, there was little power to demonstrate a linear or nonlinear relationship. Overall, there were no significant differences between groups on the psychological variables. AAS users exhibited elevated levels of antisocial personality traits, with 38% scoring in the clinically significant range. Bodybuilders reported some body weight concerns, specifically a drive for muscularity combined with a drive for a well-toned body, with no difference between AAS users and bodybuilding controls. Three AAS users and one bodybuilding control exhibited psychological disturbances, as evidenced by elevated scores on multiple psychological measures. Conclusions: The results of this preliminary study provide some evidence that high doses of AASs in men might influence certain aspects of cognition, specifically reducing complex visuospatial skills and perceptual speed. The data also suggests that endogenous testosterone influences spatial ability in healthy men in a curvilinear fashion. Further research with larger samples of AAS users is required to quantify the cognitive effects of non-medical AAS regimens. The study also contributes to the growing literature on the psychological effects of bodybuilding and AAS use. Although many AAS users and bodybuilders might display minimal psychopathology, there is likely a subgroup of individuals who exhibit clinically significant psychological disturbances. Further research is necessary to identity the nature and severity of psychological symptomatology in this population, and effective modes of treatment.
23

Growth Hormone and Anabolic Androgenic Steroids : Effects on Neurochemistry and Cognition

Grönbladh, Alfhild January 2013 (has links)
Growth hormone (GH) stimulates growth and metabolism but also displays profound effects on the central nervous system (CNS). GH affects neurogenesis and neuroprotection, and has been shown to counteract drug-induced apoptosis in the brain. Anabolic androgenic steroids (AAS), mainly abused for their anabolic and performance-enhancing properties, can cause several adverse effects, such as cardiovascular complications, sterility, depression, and aggression. GH and AAS are both believed to interact with several signaling systems in the CNS. The aim of this thesis was to further investigate the impact of GH and AAS on neurochemistry and cognitive functions. Recombinant human GH (rhGH) and the steroid nandrolone decanoate (ND) were administered, separately and in combination with each other, to male rats. The results demonstrated that administration of GH improved spatial memory, assessed in a water maze test. Furthermore, GH induced alterations of the GABAB receptor mRNA expression, density, and functionality in the brain, for example in regions associated with cognition. GH also altered the mu opioid peptide (MOP) receptor, but not the delta opioid peptide (DOP) receptor functionality in the brain. Thus, some of the GH effects on cognition may involve effects on the GABAB receptors and MOP receptors. ND, on the contrary, seemed to induce impairments of memory and also altered the GABAB receptor mRNA expression in the brain. Furthermore, ND lowered the IGF-1 plasma concentrations and attenuated the IGF-1, IGF-2, and GHR mRNA expression in the pituitary. In addition, significant effects of GH and ND were found on plasma steroid concentrations, organ weight, as well as body weight. In conclusion, this thesis contributes with further knowledge on the cognitive and neurochemical consequences of GH and ND use. The findings regarding ND are worrying considering the common use of AAS among adolescents. GH improves memory functions and affects signaling systems in the brain associated with cognition, hence the hypothesis that GH can reverse drug-induced impairments is further strengthened.
24

The Impact of Nandrolone Decanoate on Neuropeptidergic Mechanisms Related to Cognition, Aggression, Reward and Dependence

Magnusson, Kristina January 2009 (has links)
The abuse of anabolic androgenic steroids (AAS) is becoming increasingly common and may result in a range of physiological as well as psychological effects such as altered behavior in terms of increased aggression, cognitive dysfunction and addictive behavior. AAS comprise testosterone and its derivatives, of which nandrolone is one of the more common. Previous studies have shown nandrolone-induced effects in male rats on peptide levels within the Substance P (SP) system and the dynorphinergic system; these effects may be linked to some of the reported behavior alterations. The studies presented in this thesis aimed to investigate the mechanisms underlying these peptide alterations and also to further investigate neuropeptidergic effects attributed to nandrolone administration. The results display significant effects on the enzymatic conversion of SP and Dynorphin A into their bioactive metabolites SP(1-7) and Leu-enkephalin-Arg6, respectively, as a result of nandrolone treatment. More profound investigations on the dynorphinergic system displayed effects on the kappa opioid receptor density in various brain regions. There was also a significant increase in the expression of the gene transcript of prodynorphin in the hippocampus, a brain region associated with cognitive processes. In addition, impaired spatial learning and memory in the Morris water maze task following nandrolone administration was encountered. The results provide further understanding regarding neuropeptidergic mechanisms underlying AAS-induced behavioral effects.
25

Efeitos comportamentais, neuroquímicos e metabólicos do tratamento com decanoato de nandrolona em camundongos

Kalinine, Eduardo January 2011 (has links)
Desde a primeira síntese, isolamento e caracterização dos andrógenos, particularmente da testosterona em 1935, diversos homólogos sintéticos foram desenvolvidos com os objetivos de prolongar a atividade biológica, desenvolver administração parenteral e diminuir a atividade androgênica, classe denominada de esteróides anabólicos-andrógenos (EAA). Desde 1940, os EAA são utilizados na clínica para diversos tipos de doenças, destacando-se o hipogonadismo masculino e em terapias para promoção de crescimento. Também são amplamente utilizados para fins estéticos, principalmente para manutenção e promoção do ganho de massa magra corpórea. Devido ao grande aumento do consumo destes fármacos, tanto para fins esportivos como estéticos, há uma necessidade de investigar efeitos comportamentais relacionados ao seu uso exacerbado. Milhares de pessoas se auto-administram EAA em superdoses, o que gera um problema de saúde pública. Os Resultados do presente trabalho demonstram que o uso crônico dos EAA aumento do comportamento de agressivo, e sutil prejuízo da memória espacial e memória aversiva de curta duração, e na atividade exploratória em camundongos machos da linhagem CF1. Os Resultados metabólicos demonstraram que o tratamento crônico com decanoato de nandrolona (DN) não afeta a função hepática e renal, não altera a homeostasia da glicose e nem o peso corporal, mas diminui os níveis séricos de colesterol total, HDL e triglicerídeos. Os resultados neuroquímicos apontam para uma ruptura da homeostase glutamatérgica, através da alteração da captação de glutamato e do imunoconteúdo do transportador GLT 1. Em conclusão, o uso crônico com altas doses de DN causa o aumento do comportamento agressivo e diminuição na memória aversiva de curta duração. O desequilíbrio da função glutamatérgica evidenciado pela diminuição da captação de glutamato no córtex e hipocampo e do transportador GLT-1- pode ser um dos mecanismos neuroquímicos envolvidos nas alterações comportamentais induzidas pelo tratamento com o DN. / Since the first synthesis, isolation and characterization of androgens, particularly testosterone in 1935, several synthetic counterparts were developed with the objective of prolonging the biological activity, parenteral administration and decrease the androgen activity, called the class of anabolic-androgenic (AAS). Since 1940, AAS are used in the clinic for several types of diseases, especially in male hypogonadism and therapies to promote growth. Additionally, they are widely used for esthetic purposes, mainly for maintenance and promotion of lean body mass gain. Due to the large increase in consumption of these drugs, both for aesthetic purposes and sports, the investigation of behavioral effects related to its overuse is imperative. Thousands of people self-administer AAS in overdoses, a fact that creates a public health problem. The results of this study demonstrate that chronic administration of AAS cause an increase in aggressive behavior, and subtle impairment of spatial memory and short-term aversive memory in male mice strain CF1. The metabolic results showed that chronic treatment with Nandrolone Decanoate (DN) neither affect hepatic and kidney function, nor glucose homeostasis and body weight but decreased serum levels of total cholesterol, HDL and triglycerides. The neurochemical results suggest a disruption of glutamatergic homeostasis through changes in glutamate uptake and GLT1 immunocontent. In conclusion, the chronic use at high doses of DN causes increase of aggressive behavior impairs short-term avoidance memory. The imbalance of glutamatergic function evidenced by the decreased glutamate uptake in cortex and hippocampus as well as decreased immunocontent of GLT-1 may participate in the mechanisms underlying behavioral changes induced by chronic treatment with DN.
26

Efeitos comportamentais, neuroquímicos e metabólicos do tratamento com decanoato de nandrolona em camundongos

Kalinine, Eduardo January 2011 (has links)
Desde a primeira síntese, isolamento e caracterização dos andrógenos, particularmente da testosterona em 1935, diversos homólogos sintéticos foram desenvolvidos com os objetivos de prolongar a atividade biológica, desenvolver administração parenteral e diminuir a atividade androgênica, classe denominada de esteróides anabólicos-andrógenos (EAA). Desde 1940, os EAA são utilizados na clínica para diversos tipos de doenças, destacando-se o hipogonadismo masculino e em terapias para promoção de crescimento. Também são amplamente utilizados para fins estéticos, principalmente para manutenção e promoção do ganho de massa magra corpórea. Devido ao grande aumento do consumo destes fármacos, tanto para fins esportivos como estéticos, há uma necessidade de investigar efeitos comportamentais relacionados ao seu uso exacerbado. Milhares de pessoas se auto-administram EAA em superdoses, o que gera um problema de saúde pública. Os Resultados do presente trabalho demonstram que o uso crônico dos EAA aumento do comportamento de agressivo, e sutil prejuízo da memória espacial e memória aversiva de curta duração, e na atividade exploratória em camundongos machos da linhagem CF1. Os Resultados metabólicos demonstraram que o tratamento crônico com decanoato de nandrolona (DN) não afeta a função hepática e renal, não altera a homeostasia da glicose e nem o peso corporal, mas diminui os níveis séricos de colesterol total, HDL e triglicerídeos. Os resultados neuroquímicos apontam para uma ruptura da homeostase glutamatérgica, através da alteração da captação de glutamato e do imunoconteúdo do transportador GLT 1. Em conclusão, o uso crônico com altas doses de DN causa o aumento do comportamento agressivo e diminuição na memória aversiva de curta duração. O desequilíbrio da função glutamatérgica evidenciado pela diminuição da captação de glutamato no córtex e hipocampo e do transportador GLT-1- pode ser um dos mecanismos neuroquímicos envolvidos nas alterações comportamentais induzidas pelo tratamento com o DN. / Since the first synthesis, isolation and characterization of androgens, particularly testosterone in 1935, several synthetic counterparts were developed with the objective of prolonging the biological activity, parenteral administration and decrease the androgen activity, called the class of anabolic-androgenic (AAS). Since 1940, AAS are used in the clinic for several types of diseases, especially in male hypogonadism and therapies to promote growth. Additionally, they are widely used for esthetic purposes, mainly for maintenance and promotion of lean body mass gain. Due to the large increase in consumption of these drugs, both for aesthetic purposes and sports, the investigation of behavioral effects related to its overuse is imperative. Thousands of people self-administer AAS in overdoses, a fact that creates a public health problem. The results of this study demonstrate that chronic administration of AAS cause an increase in aggressive behavior, and subtle impairment of spatial memory and short-term aversive memory in male mice strain CF1. The metabolic results showed that chronic treatment with Nandrolone Decanoate (DN) neither affect hepatic and kidney function, nor glucose homeostasis and body weight but decreased serum levels of total cholesterol, HDL and triglycerides. The neurochemical results suggest a disruption of glutamatergic homeostasis through changes in glutamate uptake and GLT1 immunocontent. In conclusion, the chronic use at high doses of DN causes increase of aggressive behavior impairs short-term avoidance memory. The imbalance of glutamatergic function evidenced by the decreased glutamate uptake in cortex and hippocampus as well as decreased immunocontent of GLT-1 may participate in the mechanisms underlying behavioral changes induced by chronic treatment with DN.
27

Marcadores bioquímicos e de estresse oxidativo no fígado e nos rins de ratos submetidos a diferentes protocolos de utilização de esteroides anabolizantes / Biochemical and oxidative stress markers in the liver and kidneys of rats submitted to different protocols of anabolic steroids

Dornelles, Guilherme Lopes 18 February 2016 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Anabolic androgenic steroids (AAS) are synthetic substances derived from testosterone that promote greater muscle mass and strenght. Thus, they are used illegally to improve athletic performance of horses, dogs or athletes or to improve meat production. The doses, ranging from 10 to100 times the therapeutic recommendation, enhances the deleterious effects on various organs. The objective of this study was to evaluate the effects of different protocols (P1, P2 and P3) of boldenone undecylenate (BU) and stanozolol (ST) on markers of liver and kidney function and variables of oxidative stress in these organs. For this, 54 male Wistar rats were divided into nine groups of six animals each. Each animal received intramuscularly 5.0 mg kg-1 of BU or ST once a week for four weeks (P1); 2.5 mg kg-1 of BU or ST once a week for eight weeks (P2); and 1.25 mg kg-1 of BU or ST once a week for 12 weeks (P3). For each protocol, a control group was used (CG), and they received 0.1 ml of olive oil intramuscularly. Blood, and fragments of liver and kidney were collected for alanine aminotransferase activity (ALT), alkaline phosphatase (ALP), albumin, creatinine, cholesterol, total protein, triglycerides, urea, reactive oxygen species (ROS), thiobarbituric acid reactive substances (TBARS), total thiols (T-SH), and glutathione (GSH) evaluation. Seric ALT activity and cholesterol concentration were significantly (p<0.05) higher compared to CG when BU of protocol P1 was used. ALT activity was significantly higher (p<0.05) compared to the CG in protocol P2 when ST was used. Liver samples showed higher levels (p<0.05) of ROS and TBARS in protocols P1 and P3 when BU was used, and lower GSH activity (p<0.05) on group treated with protocol P3. Rats that have received ST under protocol P1 and P3 showed higher levels (p<0.05) of ROS, as well as increased TBARS levels in P3 but lower GSH activity in P3 (p<0.05) when compared to the CG. In the liver, the T-SH concentration was lower (p<0.05) in P2 when compared BU and ST of the CG. In renal tissues, ROS and TBARS levels were significantly higher (p<0.05) in animals that received BU under protocols P1 and P2; and GSH activity and T-SH levels were reduced in the three protocols (P1, P2 and P3). In addition, animals treated with ST occurred showed reduced renal levels of GSH levels (p<0.05) in P2 and P3. The treatment with ST also led to higher ROS levels (p<0.05) in P2 and P3, and TBARS levels in P3, but reduced concentration (p<0.05) of GSH levels in P2 and P3, and T-SH in P2 and P3. In conclusion, anabolic steroids are harmful even when used in low doses or in a few applications, since in all evaluated protocols was possible to observe changes in the redox balance in the liver and kidneys. / Esteroides anabólicos androgênicos (EAA) são substâncias sintéticas derivadas da testosterona que promovem crescimento muscular e ganho de força. Devido a isso, são utilizadas ilegalmente para melhora da performance atlética de equinos, caninos ou atletas ou para maior produção de carne. As doses variam de 10 a 100 vezes a recomendação terapêutica, o que potencializa os efeitos deletérios em diversos órgãos. O objetivo deste trabalho foi avaliar os efeitos de diferentes protocolos de administração (P1, P2 e P3) de undecilenato de boldenona (UB) e estanozolol (EST) em indicadores da função e lesão, bem como, parâmetros oxidativos hepático e renal. Para isso, foram utilizados 54 ratos Wistar, machos, distribuídos em nove grupos com seis animais cada que receberam por via intramuscular 5 mg/kg de UB ou EST uma vez por semana durante 4 semanas (P1); 2,5mg/kg de UB ou EST uma vez por semana durante 8 semanas (P2) e 1,25mg/kg de UB ou EST uma vez por semana durante 12 semanas (P3). Cada protocolo teve um grupo controle (GC) que recebeu 0,1 mL de azeite de oliva intramuscular. Posteriormente a eutanásia, realizada uma semana após o último tratamento, foi avaliada a atividade sérica da alanina aminotransferase (ALT) e fosfatase alcalina (FA), os níveis séricos de albumina, creatinina, colesterol, proteínas totais, triglicerídeos, ureia, espécies reativas de oxigênio (ERO), substâncias reativas ao ácido tiobarbitúrico (TBARS), glutationa reduzida (GSH) e tiois totais (T-SH). No protocolo P1 obteve-se atividade sérica de ALT e concentração de colesterol significativamente (p<0,05) maiores comparando-se o grupo UB com o grupo GC. O grupo EST obteve aumento significativo (p>0,05) da ALT em relação ao grupo controle no protocolo P2. No tecido hepático, comparando-se os grupos UB e GC, obteve-se níveis maiores (p<0,05) de ERO e TBARS em P1 e P3 e concentração menor (p<0,05) de GSH em P3. O grupo EST apresentou valores maiores (p<0,05) de ERO no P1 e P3, de TBARS no P3 e níveis menores (p<0,05) de GSH no P3 quando comparado ao grupo GC. A concentração hepática de T-SH foi menor (p<0,05) no P2 comparando UB e EST ao grupo GC. No tecido renal, ao comparar o grupo UB com o grupo GC obteve-se níveis significativamente maiores (p<0,05) de ERO e TBARS nos protocolos P1 e P2 e menores (p<0,05) de GSH e T-SH nos protocolos P1, P2 e P3. Comparando-se os grupos EST e GC os níveis de GSH foram menores (p<0,05) no P2 e P3. O grupo EST apresentou níveis maiores (p<0,05) de ERO nos protocolos P2 e P3, de TBARS no P3, concentração menor (p<0,05) de GSH no P2 e P3 e níveis menores de T-SH no P2 e P3 quando comparado ao grupo GC. Neste estudo foi possível concluir que os anabolizantes são prejudicias mesmo quando utilizados em baixas doses ou em poucas aplicações, visto que em todos os protocolos avaliados foi possível observar alterações do balanço redox no fígado e rins dos ratos.
28

Efeitos do metoprolol sobre as alterações histomorfológicas do coração produzidas pelo decanoato de nandrolona em ratos

Santos, Rosilene Aparecida Reis Rodrigues dos 20 August 2009 (has links)
The anabolic androgenic steroids (AAS) came from testosterone, with restricted use in medicine in some specific clinical conditions, and when correctly administrated are well tolerated. However, there is a potential risk to health the use of AAS without medical prescription and above the recommended dose, becoming evident the collateral effects. The risk of adverse cardiovascular effects increasing is a main concerning. The abusive use of anabolic androgenic steroids (AAS) is associated with left ventricular hypertrophy. The decanoate of nandrolone (nandrolone) is one of the most used AAS in the world. The regression of left ventricular hypertrophy is a point of interest because of the possible reduction of bad prognostic that it causes to the individual. Beta-blockers can revert the variations associated to ventricular remodeling and can show the progressive deterioration benefits from ventricular dysfunction. In this study was evaluated the effects of metoprolol on histomorphological profile of heart induced by AAS in rats. Four groups, each with 10 rats, were studied: 1) Control Group (C): rats that received twice a week injections of olive oil during five weeks as a control group (1 ml intramuscular);2) Nandrolone Group (N): rats that received twice a week injections of nandrolone during five weeks (15 mg/kg weight, intramuscular); 3) Metoprolol Group (M): rats that received twice a week injections of olive oil (1 ml intramuscular) during five weeks and daily injections of metoprolol (4 mg/kg weight, intraperitonial) during five weeks and 4) Nandrolone-Metoprolol Group (NM): rats that received twice a week injections of nandrolone (15 mg/kg weight, intramuscular) during five weeks and daily injections of metoprolol (4 mg/kg weight, intraperitonial) during five weeks. The animals were weighed to control body weight and heart beat frequency. The heart weight/animal weight ratio was quantified. The evaluation of ventricular remodelling was obtained through histological processing and morphological analyses, measuring miocytes diameter using HL Image 97. These microphotographies allowed the transversal diameter measurement of, at least, five ventricular fibers, with a total of 125 fibers measured by animal. The diameter of each fiber, in micrometers, was obtained in the HL Image 97 program. It was verified that the animals from Nandrolone (N) group showed a significant increasing of the ventricular fiber diameter compared with control group (C). In the association of nandrolone and metoprolol (NM) the diameter was 50 % lower than the group that received only nandrolone (N). The nandrolone decanoate promotes ventricular remodeling characterized by the increasing of myocardiocytes transversal diameter and the metoprolol associated with this nandrolone causes cardioprotective and repairing effect, decreasing the induced myocardium hypertrophy / Os esteróides anabólico-androgênicos (EAA) são derivados da testosterona, de uso exclusivo na medicina para certas condições clínicas e, quando administrados corretamente, são em geral bem tolerados. Porém existe risco potencial à saúde quando o uso dos EAA ocorre sem vigilância médica, sem indicação clínica adequada e são empregadas doses acima das recomendadas, tornando-se prováveis os efeitos colaterais indesejados. Especialmente preocupante é o aumento do risco de efeitos adversos cardiovasculares. O uso abusivo de esteróides anabolizantes está associado ao aparecimento de hipertrofia ventricular esquerda (HVE). O decanoato de nandrolona (NAN) é um dos EAA mais utilizados no mundo. O tratamento visando a regressão da HVE vem se tornando, nos últimos tempos, um foco de interesse, principalmente pela possível redução do mau prognóstico que ela traz. Os bloqueadores beta-adrenérgicos podem reverter às alterações associadas a este tipo de remodelamento e evidenciam seus benefícios na inibição da deterioração progressiva da disfunção ventricular. Neste estudo, avaliamos os efeitos do metoprolol sobre as alterações histomorfológicas do coração produzidas pelo NAN. Foram estudados quatro grupos de ratos com 10 animais em cada um deles e assim identificados: 1) Grupo Controle (C): ratos que receberam injeção duas vezes por semana de óleo de oliva por cinco semanas como grupo controle (1ml, via intramuscular); 2) Grupo Nandrolona (N): ratos que receberam injeção duas vezes por semana de NAN por cinco semanas (15mg/kg de peso, intramuscular); 3) Grupo Metoprolol (M): ratos que receberam injeção, duas vezes por semana, de óleo de oliva, por cinco semanas (1ml, intramuscular) e injeção diária de metoprolol por cinco semanas (4mg/kg de peso, intra peritoneal) e 4) Grupo Nandrolona-Metoprolol (NM): ratos que receberam injeção, duas vezes por semana, de NAN, por cinco semanas (15mg/kg de peso, intramuscular) e injeção diária de metoprolol por cinco semanas (4mg/kg de peso, intra peritoneal). Os animais foram controlados quanto ao peso e à frequência cardíaca. A relação entre o peso cardíaco e o peso corporal também foram quantificados. A avaliação do remodelamento ventricular foi obtida por processamento histológico e análises morfométricas, medindo-se o diâmetro dos miócitos usando o software HL Image. Por meio da análise de imagem computacional foram mensurados o diâmetro de 125 fibras musculares ventriculares de cada animal. Verificou-se que os animais do grupo Nandrolona(N) apresentavam aumento significante do diâmetro das fibras musculares ventriculares em relação ao grupo controle (C). Na associação da nandrolona com o metoprolol (N-M) o diâmetro foi 50% menor em relação ao grupo que recebeu somente nandrolona (N). O decanoato de nandrolona causa remodelamento ventricular caracterizado por aumento do diâmetro transversal dos cardiomiócitos e o metoprolol, associado a este anabolizante, exerce efeito modulador neste processo reduzindo a HVE induzida. / Mestre em Ciências da Saúde
29

Efeitos comportamentais, neuroquímicos e metabólicos do tratamento com decanoato de nandrolona em camundongos

Kalinine, Eduardo January 2011 (has links)
Desde a primeira síntese, isolamento e caracterização dos andrógenos, particularmente da testosterona em 1935, diversos homólogos sintéticos foram desenvolvidos com os objetivos de prolongar a atividade biológica, desenvolver administração parenteral e diminuir a atividade androgênica, classe denominada de esteróides anabólicos-andrógenos (EAA). Desde 1940, os EAA são utilizados na clínica para diversos tipos de doenças, destacando-se o hipogonadismo masculino e em terapias para promoção de crescimento. Também são amplamente utilizados para fins estéticos, principalmente para manutenção e promoção do ganho de massa magra corpórea. Devido ao grande aumento do consumo destes fármacos, tanto para fins esportivos como estéticos, há uma necessidade de investigar efeitos comportamentais relacionados ao seu uso exacerbado. Milhares de pessoas se auto-administram EAA em superdoses, o que gera um problema de saúde pública. Os Resultados do presente trabalho demonstram que o uso crônico dos EAA aumento do comportamento de agressivo, e sutil prejuízo da memória espacial e memória aversiva de curta duração, e na atividade exploratória em camundongos machos da linhagem CF1. Os Resultados metabólicos demonstraram que o tratamento crônico com decanoato de nandrolona (DN) não afeta a função hepática e renal, não altera a homeostasia da glicose e nem o peso corporal, mas diminui os níveis séricos de colesterol total, HDL e triglicerídeos. Os resultados neuroquímicos apontam para uma ruptura da homeostase glutamatérgica, através da alteração da captação de glutamato e do imunoconteúdo do transportador GLT 1. Em conclusão, o uso crônico com altas doses de DN causa o aumento do comportamento agressivo e diminuição na memória aversiva de curta duração. O desequilíbrio da função glutamatérgica evidenciado pela diminuição da captação de glutamato no córtex e hipocampo e do transportador GLT-1- pode ser um dos mecanismos neuroquímicos envolvidos nas alterações comportamentais induzidas pelo tratamento com o DN. / Since the first synthesis, isolation and characterization of androgens, particularly testosterone in 1935, several synthetic counterparts were developed with the objective of prolonging the biological activity, parenteral administration and decrease the androgen activity, called the class of anabolic-androgenic (AAS). Since 1940, AAS are used in the clinic for several types of diseases, especially in male hypogonadism and therapies to promote growth. Additionally, they are widely used for esthetic purposes, mainly for maintenance and promotion of lean body mass gain. Due to the large increase in consumption of these drugs, both for aesthetic purposes and sports, the investigation of behavioral effects related to its overuse is imperative. Thousands of people self-administer AAS in overdoses, a fact that creates a public health problem. The results of this study demonstrate that chronic administration of AAS cause an increase in aggressive behavior, and subtle impairment of spatial memory and short-term aversive memory in male mice strain CF1. The metabolic results showed that chronic treatment with Nandrolone Decanoate (DN) neither affect hepatic and kidney function, nor glucose homeostasis and body weight but decreased serum levels of total cholesterol, HDL and triglycerides. The neurochemical results suggest a disruption of glutamatergic homeostasis through changes in glutamate uptake and GLT1 immunocontent. In conclusion, the chronic use at high doses of DN causes increase of aggressive behavior impairs short-term avoidance memory. The imbalance of glutamatergic function evidenced by the decreased glutamate uptake in cortex and hippocampus as well as decreased immunocontent of GLT-1 may participate in the mechanisms underlying behavioral changes induced by chronic treatment with DN.
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Anabolic Androgenic Steroids : Effects on Neuropeptide Systems in the Rat Brain

Hallberg, Mathias January 2005 (has links)
<p>Anabolic-androgenic steroids (AAS) have been used in clinics for decades. The misuse of AAS has previously been attributed merely to sport athletes, taking AAS with intentions to increase muscle mass, enhance physical performance and to improve results in competitions. Today, the misuse of AAS has spread to adolescents and young adults not connected to sports. Alarmingly, many reports are pointing at severe psychiatric adverse effects among AAS abusers, which include mood swings, mania, anxiety, depression and aggression. Numerous examples of severe and often unprovoked violence and brutal crimes have been connected to AAS abuse and there is a strong need for a better understanding of the underlying biochemical events that might account for the adverse behaviors induced by AAS. The general aim of this thesis was to study the effect of chronic AAS administration on neuropeptide circuits in the rat brain associated with the regulation of rewarding effects, memory, anxiety, depression and aggression, using nandrolone decanoate as a prototype AAS.</p><p>Results demonstrated that daily administration of AAS to rats in doses comparable to those taken by AAS abusers, in certain brain structures significantly affected, <i>a</i>) the levels of the opioid peptides dynorphin B and Met-enkephalin-Arg<sup>6</sup>Phe<sup>7</sup>, <i>b</i>) the levels of the tachykinin substance P (SP), <i>c</i>) the density of the SP neurokinin 1 (NK1) receptor, <i>d</i>) the level of the SP metabolite SP<sub>1-7 </sub>that frequently exerts opposite effects to SP, <i>e</i>) the SP<sub>1-7 </sub>generating enzyme substance P endopeptidase (SPE) and finally, <i>f</i>) the levels of the neuropeptide calcitonin gene-related peptide (CGRP) often co-localized with SP. The alterations seen in the levels and activities of these neurochemical components are in many aspects compatible with behaviors typified among AAS abusers.</p>

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