The Effects of Testosterone Propionate on the Testes, Seminal Vesicles and Prostate of Intact and Castrate Rats

Much work has been done upon the response of immature rats\u27 testes and accessories to male hormones. The treatments in general have been over a long period of time. In this research, the effects of testosterone propionate on the testes and accessories were observed after injection of testosterone propionate for a period of 14 days. The objectives being: I. To study the normal condition of the testes and accessory sex organs of the rat which may be compared with modifications of these organs in experimental animals. II. To observe the responses that the male testes and accessories make after the injection of testosterone propionate into 22 days of age rats for a period of 14 days. III. To determine if the effects of testosterone propionate are parallel to the effects of the male hormone secreted by the testes. IV. To show how castration affect the accessory sex organs, and find out if testosterone propionate injection will prevent the appearance of castrate characteristics

Modulation of the cytosolic androgen receptor in striated muscle by sex steroids

The influence of orchiectomy (GDX) and steroid administration on the level of the cytosolic androgen receptor in the rat levator ani muscle and in rat skeletal muscles (tibialis anterior and extensor digitorum longus) was studied. Androgen receptor binding to muscle cytosol was measured using H-3 methyltrienolone (R1881) as ligand, 100 fold molar excess unlabeled R1881 to assess nonspecific binding, and 500 fold molar excess of triamcinolone acetonide to prevent binding to glucocorticoid and progestin receptors. Results demonstrate that modification of the levels of sex steroids can alter the content of androgen receptors of rat striated muscle. Data suggest that: (1) cytosolic androgen receptor levels increase after orchiectomy in both levator ani muscle and skeletal muscle; (2) the acute increase in receptor levels is blocked by an inhibitor of protein synthesis; and (3) administration of estradiol-17 beta to castrated animals increases receptor binding in levator ani muscle but not in skeletal muscle

Growth and Agonistic Responses of Yaffa Breed Cockerels Administered Testosterone Propionate

The effect of birds’ duration of administration (duration of exposure) to exogenous Testosterone propionate on total weight gain (TWG) and agonistic behaviours (ABs) were evaluated in the Teaching and Research farm of the University of Ibadan, in Southwestern Nigeria. Testosterone propionate (TP) was administered once weekly, to Yaffa breed cockerels in T1,T2,T3,T4,T5 (for 8,12,16,18 and 20 weeks respectively).Birds in T6,received no testosterone propionate.ABs were evaluated twice daily, on a scale of 1-4,where 1 stood for ‘least agonistic’ and 4 stood for ‘very agonistic’. Agonistic acts like Head and feather pecks,kicks,chases and pushes were visually evaluated  TP-administered birds had significantly (p<0.05) higher ABs and TWGs than the birds in the Control. Higher ABs however did not affect TWG and other growth parameters negatively Keywords: Cockerels, Testosterone propionate, Growth, Agonistic behaviour

Impact of Neonatal Manipulation of Androgen Receptor Function on Endocrine-Metabolic Programming in the Juvenile Female Rat

The impact of neonatal androgen receptor (AR) stimulation/blockage, due to testosterone propionate (TP)/AR antagonist treatment, on individual anthropometry and neuroendocrine-metabolic function was evaluated in the juvenile female rat. Pups (age 5 days) were s.c. injected with TP (1.25 mg), flutamide (F; 1.75 mg), and TP + F or vehicle (control, CT) and studied on day 30 of age. Body weight (BW), parametrial adipose tissue (PMAT) mass, food intake, adipoinsular axis, and steroidogenic functions were examined. Opposite to TP-rats, F-treated rats developed hypophagia, grew slowly (BW and PMAT), and displayed heightened peripheral insulin sensitivity. These F effects were abrogated in TP + F animals. Accordingly, TP rats displayed hyperleptinemia, an effect fully prevented by F cotreatment. Finally, androgen-treated animals bore an irreversible ovarian dysfunction (reduced circulating levels of 17HOP4 and ovary 17HOP4 content and P450c17 mRNA abundance). These data indicate that early stimulation of AR enhanced energy store, blockage of AR activity resulted in some beneficial metabolic effects, and neonatally androgenized rats developed a severe ovarian dysfunction. Our study highlights the important role of AR in the early organizational programming of metabolic and neuroendocrine functions.Fil: Ongaro, Luisina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Giovambattista, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; ArgentinaFil: Spinedi, Eduardo Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Multidisciplinario de Biología Celular. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Multidisciplinario de Biología Celular. Universidad Nacional de La Plata. Instituto Multidisciplinario de Biología Celular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - la Plata. Centro de Endocrinología Experimental y Aplicada. Universidad Nacional de la Plata. Facultad de Cs.médicas. Centro de Endocrinología Experimental y Aplicada; Argentin

Effect of androgen treatment during foetal and/or neonatal life on ovarian function in prepubertal and adult rats

We investigated the effects of different windows of testosterone propionate (TP) treatment during foetal and neonatal life in female rats to determine whether and when excess androgen exposure would cause disruption of adult reproductive function. Animals were killed prepubertally at d25 and as adults at d90. Plasma samples were taken for hormone analysis and ovaries serial sectioned for morphometric analyses. In prepubertal animals, only foetal+postnatal and late postnatal TP resulted in increased body weights, and an increase in transitory, but reduced antral follicle numbers without affecting total follicle populations. Treatment with TP during both foetal+postnatal life resulted in the development of streak ovaries with activated follicles containing oocytes that only progressed to a small antral (smA) stage and inactive uteri. TP exposure during foetal or late postnatal life had no effect upon adult reproductive function or the total follicle population, although there was a reduction in the primordial follicle pool. In contrast, TP treatment during full postnatal life (d1-25) resulted in anovulation in adults (d90). These animals were heavier, had a greater ovarian stromal compartment, no differences in follicle thecal cell area, but reduced numbers of anti-Mullerian hormone-positive smA follicles when compared with controls. Significantly reduced uterine weights lead reduced follicle oestradiol production. These results support the concept that androgen programming of adult female reproductive function occurs only during specific time windows in foetal and neonatal life with implications for the development of polycystic ovary syndrome in women

Differential Effects of Neonatal Testosterone Treatment on Aggression in Two Selection Lines of Mice

Selection lines of mice, artificially selected for aggression based upon the attack latency score (ALS), were used. In order to determine the relative contribution of neonatal testosterone (T) in the development of aggression, we vary the plasma-T level in males of both selection lines on the day of birth. At 14 weeks the ALS was measured. Neonatal T treatment results in a reduction of aggression in the long attack latency (LAL) line, whereas aggressive behaviour of the short attack latency (SAL) line is not affected. Both selection lines show reduction in testicular weight, although the total amount of T-producing Leydig cells was not affected. Neonatal T may cause a permanent reduction in aggressive behaviour in the LAL line only, probably due to differential appearance of critical periods. It is suggested that the difference in aggressive behaviour between SAL and LAL selection lines is due to a prenatally determined difference in neonatal T sensitivity of the brain.

Gonadal hormones, but not sex, affect the acquisition and maintenance of a Go/No-Go odor discrimination task in mice

In mice, olfaction is crucial for identifying social odors (pheromones) that signal the presence of suitable mates. We used a custom-built olfactometer and a thirst-motivated olfactory discrimination Go/No-Go (GNG) task to ask whether discrimination of volatile odors is sexually dimorphic and modulated in mice by adult sex hormones. Males and females gonadectomized prior to training failed to learn even the initial phase of the task, which involved nose poking at a port in one location obtaining water at an adjacent port. Gonadally intact males and females readily learned to seek water when male urine (S+) was present but not when female urine (S−) was present; they also learned the task when non-social odorants (amyl acetate, S+; peppermint, S−) were used. When mice were gonadectomized after training the ability of both sexes to discriminate urinary as well as non-social odors was reduced; however, after receiving testosterone propionate (castrated males) or estradiol benzoate (ovariectomized females), task performance was restored to pre-gonadectomy levels. There were no overall sex differences in performance across gonadal conditions in tests with either set of odors; however, ovariectomized females performed more poorly than castrated males in tests with non-social odors. Our results show that circulating sex hormones enable mice of both sexes to learn a GNG task and that gonadectomy reduces, while hormone replacement restores, their ability to discriminate between odors irrespective of the saliency of the odors used. Thus, gonadal hormones were essential for both learning and maintenance of task performance across sex and odor type.We thank David Giese for help in programming the apparatus used in GNG testing and Alberto Cruz-Martin for comments on an early version of the manuscript. This work was supported by NIDCD grant DC008962 to JAC. (DC008962 - NIDCD grant)Accepted manuscrip

Sex steroids do not affect muscle weight, oxidative metabolism or cytosolic androgen reception binding of functionally overloaded rat Plantaris muscles

The effects of sex steroids on muscle weight and oxidative capacity of rat planaris muscles subjected to functional overload by removal of synergistic muscles were investigated. Ten weeks after bilateral synergist removal, plantaris muscles were significantly hypertrophic compared with unoperated controls. After this period, the ability of the muscles to oxide three substrates of oxidative metabolism was assessed. Experimental procedures are discussed and results are presented herein. Results suggest a lack of beneficial effect of sex hormone status on the process of hypertrophy and on biochemical changes in overloaded muscle. Such findings are not consistent with the idea of synergistic effects of sex steroids and muscle usage

Effects of testosterone propionate on growth, survival and sex-ratio of African catfish (Clarias gariepinus Burchell)

For studying the effects of different levels of testosterone propionate on growth, survival and sex-ratio, five different doses such as 125, 100, 75, 50, 25 mg hormone per kg feed were administered to 5-day old Clarias gariepinus fry through diet for a period of 40 days. The growth performance in terms of weight and length gain of the fry receiving 100 and 75 mg hormone per kg feed were significantly higher than those receiving 50, 25 and 0 (untreated control) mg hormone per kg feed. The groups of fry treated with higher doses of hormone showed lower survival compared to those with lower doses of hormone. The frequency of male fish in the entire hormone treated groups except the 125mg/kg group, was significantly higher than that of the expected frequency of male fish in a normal population. The highest frequency of male fish, 92.08%, was obtained with the diet containing 50 mg hormone/kg diet however, the highest levels of hormone (125mg/kg diet) resulted in relatively lower frequency of male fish