Utilizaram-se 27 ratos Wistar, machos com 98 dias de idade, originados do Biotério da FMVZ-USP, com o objetivo de avaliar os possíveis efeitos do diabetes mellitus, sobre a função reprodutiva relacionada ao macho.Os animais foram divididos em três grupos, grupo A (GA) constituído de 10 animais sadios, grupo B (GB) constituído de oito ratos Wistar, com diabetes mellitus induzida quimicamente através da administração intraperitonial de estreptozotocina (65mg/Kg) e grupo C (GC) constituído por nove animais com diabetes mellitus induzida quimicamente pela administração intraperitonial de estreptozotocina (65mg/Kg), associada a insulinoterapia (3UI/rato por dia). Após quatro dias da administração da droga (GB e GC), os animais pertencentes ao grupo C (GC) receberam insulinoterapia (três IU/rato/dia) durante 42 dias. No final do experimento (46 dias após a administração da estreptozotocina), os animais foram sacrificados e foram observados os seguintes resultados; O diabetes mellitus leva ao aumento da glicemia, diminuição do peso corpóreo, diminuição do peso e tamanho testicular, diminuição das concentrações séricas de testosterona e FSH. Porém através da avaliação dos níveis séricos de inibina B, foi constatado que o diabetes não promove nem redução, nem aumento das concentrações séricas desse hormônio. Conclui-se também que a reposição exógena de insulina foi capaz de impedir a diminuição do peso corporal, redução do peso testicular, diminuição dos níveis de testosterona e FSH, porém apesar da insulinoterapia ter impedido a diminuição do peso corpóreo, não foi capaz de proporcionar o mesmo desenvolvimento corporal observado nos animais controle. / The objective of the present experiment was to evaluate the possible effect of diabetes mellitus, on the reproductive function in male rats. Towards this end, 27 male Wistar rats (98 days old), housed at the FMVZ-USP animal holding facility, were randomly assigned into three groups: Group A (GA) consisting of 10 healthy animals; Group B(GB) consisting of eight Wistar rats, with diabetes mellitus chemically induced through the intraperitoneal administration of estreptozotocin (65mg/Kg); and C group (GC) constituted by nine animals with diabetes mellitus chemically induced by the intraperitoneal administration of estreptozotocin (65mg/Kg), associate to an insulin treatment (3IU/rat per day for 42 days) that begun 4 days after the streptozotocin administration. Animals were euthanized 46 days after the administration of the estreptozotocin and the following results were obtained: diabetes mellitus led to an increase of the glicemia, reduction of the corporeal weight, decreased testicular wheight, serum concentrations of testosterone and FSH. No effect of diabeted were found for the serum levels of inhibin B. Results suggested that the exogen replacement of insulin was capable of hindering the reduction on corporal weight, reduction of testicular weight and reduction of the testosterone levels and FSH. On the other hand despite the fact that insulin treatament was capable of avoiding the reduction on bofy weight, it was not capable to provide similar body development observed in the normal animals.

Utilizaram-se 27 ratos Wistar, machos com 98 dias de idade, originados do Biotério da FMVZ-USP, com o objetivo de avaliar os possíveis efeitos do diabetes mellitus, sobre a função reprodutiva relacionada ao macho.Os animais foram divididos em três grupos, grupo A (GA) constituído de 10 animais sadios, grupo B (GB) constituído de oito ratos Wistar, com diabetes mellitus induzida quimicamente através da administração intraperitonial de estreptozotocina (65mg/Kg) e grupo C (GC) constituído por nove animais com diabetes mellitus induzida quimicamente pela administração intraperitonial de estreptozotocina (65mg/Kg), associada a insulinoterapia (3UI/rato por dia). Após quatro dias da administração da droga (GB e GC), os animais pertencentes ao grupo C (GC) receberam insulinoterapia (três IU/rato/dia) durante 42 dias. No final do experimento (46 dias após a administração da estreptozotocina), os animais foram sacrificados e foram observados os seguintes resultados; O diabetes mellitus leva ao aumento da glicemia, diminuição do peso corpóreo, diminuição do peso e tamanho testicular, diminuição das concentrações séricas de testosterona e FSH. Porém através da avaliação dos níveis séricos de inibina B, foi constatado que o diabetes não promove nem redução, nem aumento das concentrações séricas desse hormônio. Conclui-se também que a reposição exógena de insulina foi capaz de impedir a diminuição do peso corporal, redução do peso testicular, diminuição dos níveis de testosterona e FSH, porém apesar da insulinoterapia ter impedido a diminuição do peso corpóreo, não foi capaz de proporcionar o mesmo desenvolvimento corporal observado nos animais controle. / The objective of the present experiment was to evaluate the possible effect of diabetes mellitus, on the reproductive function in male rats. Towards this end, 27 male Wistar rats (98 days old), housed at the FMVZ-USP animal holding facility, were randomly assigned into three groups: Group A (GA) consisting of 10 healthy animals; Group B(GB) consisting of eight Wistar rats, with diabetes mellitus chemically induced through the intraperitoneal administration of estreptozotocin (65mg/Kg); and C group (GC) constituted by nine animals with diabetes mellitus chemically induced by the intraperitoneal administration of estreptozotocin (65mg/Kg), associate to an insulin treatment (3IU/rat per day for 42 days) that begun 4 days after the streptozotocin administration. Animals were euthanized 46 days after the administration of the estreptozotocin and the following results were obtained: diabetes mellitus led to an increase of the glicemia, reduction of the corporeal weight, decreased testicular wheight, serum concentrations of testosterone and FSH. No effect of diabeted were found for the serum levels of inhibin B. Results suggested that the exogen replacement of insulin was capable of hindering the reduction on corporal weight, reduction of testicular weight and reduction of the testosterone levels and FSH. On the other hand despite the fact that insulin treatament was capable of avoiding the reduction on bofy weight, it was not capable to provide similar body development observed in the normal animals.

Fetal testosterone (FT) exposure influences sexual differentiation and may promote well-established sex differences in externalizing (EXT) behavior. Although puberty may be a critical period for these effects, it is unknown how FT exposure influences EXT as a function of pubertal development. We used a longitudinal, multi-sample design to test the relationships between two proxy indices of FT exposure and EXT as a function of age and pubertal development (approximately ages 6, 9, 11, 14, and 16). Twin data were used to approximate FT exposure (TT-FT) because testosterone is thought to cross the intrauterine membrane and cause variability in co-twin gonadal hormone exposure, with increasing exposure for males and participants with male co-twins. Increasing number of older siblings may also approximate increasing FT exposure (SI-FT), although existing research has yet to disentangle possible postnatal socialization effects from potential FT exposure using this variable. Given that biologically related siblings share a fetal and social environment while non-biologically related siblings simply share a social environment, we tested the independent effect of SI-FT on EXT using a sibling adoption design. Across four independent samples, SI-FT and TT-FT predicted externalizing for males alone. SI-FT predicted EXT over-and-above socialization influences and interacted with pubertal development in two independent samples, with elevated EXT for those in mid-late puberty that were exposed to increased FT. TT-FT predicted EXT differentially as a function of developmental period. Our data are consistent with the notion that exposure to FT promotes sexually differentiated, sexually selected behavior during reproductively relevant periods.

The purpose of this study was to monitor cardiovascular and endocrine changes in sedentary and training females during a six week period, and to assess the accuracy of a new, low-invasive sampling methodology (electrosonophoresis). Changes in fitness were measured using oxygen consumption (VO2). The impact on VO2 of sleep quality, sleep duration and alcohol consumption (recorded in sleep logs) was assessed. Cortisol, testosterone and growth hormone levels in plasma were monitored for acute changes following fitness tests, and chronic changes related to training, oral contraceptive use or alcohol consumption. Hormone concentrations in blood and saliva samples were compared to those in interstitial fluid (obtained using electrosonophoresis) to investigate the accuracy of electrosonophoresis. Mean VO2 increased by 3.3 ± 1.3mL/kg/min between Week 1 and Week 5 and the changes detected in heart rate (HR) during the fitness tests suggest that aerobic fitness of the training participants increased across the study. No significant associations between sleep quality, sleep duration or alcohol consumption and VO2 were detected. No acute changes in plasma hormone concentrations following fitness tests were detected. No chronic changes in plasma cortisol or testosterone concentrations were detected, although a non-significant trend towards increased plasma GH levels in training participants was detected. Resting plasma cortisol levels were significantly lower in oral contraceptive users compared with non-users. Plasma testosterone and growth hormone levels were unaffected by oral contraceptive use. Alcohol consumption had no acute detectable effects on plasma concentrations of the three hormones. Plasma testosterone levels were higher in participants who abstained from alcohol, and higher plasma growth hormone levels were detected in heavy drinkers. These results contrast with published reports. Concentrations of the three hormones in interstitial fluid and plasma exhibited highly significant positive correlations (r2 > 0.98) with an interstitial fluid:plasma concentration ratio of about 1:10 in each case. Equations to predict plasma concentrations of cortisol, testosterone and growth hormone from interstitial fluid concentrations have been derived. The electrosonophoretic method apparently provides an accurate, painless, low-invasive method for prediction of the plasma levels of these three hormones. This technology has far-reaching implications for research in human, animal and biomedical fields.

Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.

The purpose of the present study was to test the acute effects of a dietary supplement, having as its major ingredient an extract of ginseng, on grip strength, lower body power output, cardiovascular markers, metabolic markers, hormones, and mood state. Twelve experienced resistance-trained men (28.3 ± 5.7 yrs) were randomly administered placebo (P), single dose (SD) and double dose (DD) of the supplement on separate days. Diet and activity levels were kept constant across testing days. On each day, subjects began with the Profile of Mood States (POMSpre1), blood draws (BDpre1), blood pressure (BPpre1), and heart rate (HRpre1) assessments, then ingested the drink and sat quietly for 30 minutes. BDpre2, BPpre2, and HR pre1 were then taken. Subjects performed the grip strength and cycle ergometer tests followed immediately by BDpost, HRpost, and BPpost and POMSpost. The testing session ended with blood draws, heart rates, and blood pressures being taken 30 (post30), 60 (post60), 120 (post120) and 180 (post180) minutes post exercise. Grip strength did not differ between P, SD, or DD treatments. Cycle ergometry peak power (PP), average power (AP) and total work (TW) were significantly higher for the SD and DD than P; however, no significant difference existed between SD and DD treatments. For LH and T significant differences were found among all treatment conditions. There were no significant treatment effects for HR, BP, glucose, insulin, lactate, GH or PRL or for the POMS. There was a significant treatment*time interaction for ACTH (p < .05). Post hoc analysis indicated that at Tpost ACTH was significantly lower for D treatment vs P or S treatments (p < .05) and at Tpost60 ACTH was significantly lower for S and D treatments vs P treatment (p < .05). There was significant differences in C between the D treatment (260.45 ± 15.58 nmol•L-1) and the P (336.08 ± 27.59 nmol•L-1) and S (311.14 ± 21.01 nmol•L-1) treatments (p < .001). There was a significant difference for T:C ratio values among P (0.0810 ± 0.0090), S (0.0960 ± 0.0130) and D (0.1410 ± 0.0190) treatments (p < .001). Acute ingestion of a polynutrient supplement containing a standardized ginseng tract, was able to increase PP, AP, TW LH, and testosterone and decrease ACTH and cortisol. No significant effects were found for GH, PRL, insulin, glucose, lactate, HR, BP or POMS scores. Acute ingestion of a polynutrient supplement was able to increase performance and the anabolic environment in resistance trained men.

In the stallion, inconsistent sexual behavior and variable semen quality are common. This reproductive variability has been attributed to differences in circulating hormone concentrations. In order to further examine this relationship, 7 miniature stallions were observed for sexual behavior and semen characteristics. Blood was also drawn from each stallion 15 min before mating (time -15), immediately following ejaculation (time 0) and at times following ejaculation (times +15, +30, and +60). Plasma was later analyzed for concentrations of testosterone (T), estrone sulphate (ES) and cortisol. Semen was evaluated for volume, sperm concentration and progressive motility. Sexual behavior was quantified by assigning a libido score to each stallion, recording reaction time and the number of jumps required for ejaculation. Upon statistical analysis, data revealed both ES and cortisol increased at the time of semen collection (P < 0.05), while T did not. Regression analysis revealed that ES and the ratio of ES to T at times -15, +30, and +60 were negatively correlated to libido scores. Additionally, a positive relationship was found between ES at times -15 and +60 and reaction time, as well as between cortisol at times -15, 0, and +15 and libido scores. No relationship was observed between T and sexual behavior. However, T at time -15 was positively correlated to progressive motility, and the ratio of ES/T at time -15 was negatively correlated to progressive motility. No other association was detected between ejaculate parameters and hormone concentrations. These results not only serve to enhance understanding of stallion hormone profiles, but also provide further insight into the hormonal control of sexual behavior and sperm production. This knowledge can be used to generate improved management techniques for stallions that are inconsistent in sexual behavior and sperm output.

The ability of an animal to respond and adapt to stimuli is necessary for its survival and involves plasticity and coordination of multiple levels of biological organization, including behavior, tissue organization, hormones, and gene expression. Each of these levels of response is complex, and none of them responds to stimuli in isolation. Thus, to understand how each system responds, it is necessary to consider its role in the context of the entire organism. Here, I have used the African cichlid fish Astatotilapia burtoni and its extraordinary phenotypic plasticity to investigate how animals respond to a change in social status from subordinate to dominant and attempted to integrate these multiple levels of biological response, as well as the roles of several candidate neuromodulators,. First, I have described how male A. burtoni become more aggressive and reproductive during their transition to dominance as well as increasing circulating levels of testosterone and estradiol and the histological organization of their testes. I then mapped the distribution of expression of two behaviorally relevant neuropeptides, arginine vasotocin and isotocin, and their respective receptors, throughout the A. burtoni brain, and found that they were highly expressed in several brain areas important for social behavior and decision-making. I then investigated the role of arginine vasotocin in social status and behavior via pharmacological manipulation and qPCR, showing the importance of arginine vasotocin in controlling the transition to dominance. Lastly, I investigated the role of aromatase, testosterone, and estradiol in male A. burtoni, both in stable dominant males and in males as they transition to dominance, using pharmacological manipulation and quantitative radioactive in situ hybridization, illustrating that estradiol synthesis during dominance is dependent on aromatase activity and necessary for aggressive behavior. / text

published_or_final_version / abstract / Medicine / Master / Master of Philosophy