Effect of prolactin on accessory sex organs of prepuberal male albino rats: an in vitro study.

The in vitro studies on the effect of hypophysial gonadotropins (PRL, FSH, LH) on the maturation events of accessory sex organs in prepuberal male rats revealed that prolactin (PRL) alone has both direct as well as androgen mediated effect on the maturation activities. The effect of PRL is age dependent and it had higher activation on the gland system than the duct system.     

Effects of estrogen on growth of androgen-responsive rat prostatic tumor (R 3327)

It has been known that estrogen has synergistic effects with androgen on growth of normal male accessory sex organs of rats. The present study was therefore undertaken to examine the effects of estrogen on androgen-responsive rat Dunning R 3327 prostatic tumor. The weight of male accessory sex organs was suppressed by estrogen on growth of treatment, but synergistic effects of estrogen and androgen on these organs were seen following combined treatment with androgen and estrogen. In contrast to the effects of estrogen on accessory sex organs, estrogen influenced a R 3327 tumor only in the negative direction regardless of whether androgen was injected simultaneously or not. When the dihydrotestosterone injection was reduced from 500 to 100 micrograms/rat/day after the tumor appeared as subcutaneous nodules, the weight of the accessory sex organs was similar to that of the control animals. However, this amount of dihydrotestosterone increased tumor growth equally when compared to those treated with a pharmacological dose of dihydrotestosterone. Therefore, the response of R 3327 tumor to androgen was different from that of the accessory sex organs.     

Male contraception properties of a new synthetic steroid derivative (danazol) in Rattus rattus rufescens

Chronic administration of Danazol (25 mg/kg body wt) caused lesions in the testes of Rattus rattus Rufescens. Depletion of spermatocytes, spermatids and spermatozoa was conspicuous. Impairment of Leydig cell function was correlated with reduced cell size and depressed accessory sex organ weights. Epididymal cell height was greatly reduced. The lumen was devoid of spermatozoa. Danazol administration inhibited the synthesis of RNA, protein, sialic acid in the testes and accessory sex organs. Total cholesterol of the testes was increased, whereas the acid phosphatase enzyme activity was reduced. Testosterone propionate did not enhance the growth of accessory sex organs in castrated rats receiving Danazol. In conclusion, Danazol inhibits the system of steroidogenesis and spermatogenesis in Rattus rattus, when treated chronically for a period of 40 days. These effects are reversible after 60 days of cessation of drug administration.     

Localization,metabolism, and binding of estrogens in the male rat

Estrogen assimilation by male Wistar rats was examined in these studies in several accessory sex organs (seminal vesicles and anterior, dorsal, lateral, and ventral prostates) as well as in a variety of nonaccessory sex organs. When [³H]estradiol was injected into intact 3- to 4-month-old rats in a pulse dose, no selective accumulation of radioactivity recovered as estradiol was found in the accessory sex glands when compared to other organs. This was due at least in part to the metabolism of estradiol to estrone and to the relatively low concentration of high affinity estrophilic molecules in the accessory sex organs. The order for the rate of formation of estrone from estradiol in tissues obtained from intact animals was ventral prostate > lateral and dorsal prostate > anterior prostate and seminal vesicles. Steroid specificity studies for cytosol estradiol binding by the ventral prostate and seminal vesicles revealed that estrophilic molecules exist in these organs. Based on Scatchard plot analyses in 24-h castrates, the number of available estradiol binding sites was too low in the ventral prostate to quantify accurately, but the seminal vesicles contained distinctly more estrophilic activity than the ventral prostate. The affinity for the seminal vesicle cytosol estradiol-estrophile binding exceeded that quantified for the seminal vesicle dihydrotestosterone-androphile reaction while the number of estradiol binding sites was less than that quantified for dihydrotestosterone. In relation to the accessory sex organs of other species, the rat seminal vesicles have a relatively small amount of cytosol estrophile. The findings that the seminal vesicles catabolize less estradiol and contain significantly more estrophilic activity than the ventral prostate is consistent with and offers insight into the noted estrogenic sensitivity of the seminal vesicles and lack thereof in the rat ventral prostate. With aging of the rat from 3–4 months to 22–26 months, the affinity of the seminal vesicle estradiol-estrophile interaction was unchanged but the number of binding sites increased significantly.     

The effect of pituitary homografts on the accessory sex organs and serum hormonal levels with or without androgen in mature male rats

The effect of pituitary homografts on the accessory sex organs and hormonal levels were studied in Wistar mature male rats. Grafted rats were further divided into four experiments: rats were bled once daily via a jugular vein cannula for seven days to investigate when serum prolactin began to rise after transplantation. rats were decapitated on the seventh day after transplantation to test whether 7 days were long enough to show the effect of pituitary grafts on the weight of prostate and seminal vesicles. rats were orchiectomized or orchiectomized and adrenalectomized on the seventh day after transplantation and then decapitated 4 weeks later to test a long term action of pituitary grafts and hormonal levels on the accessory sex organs without androgen. Rats grafted with several pieces of muscle were used as controls in each experiment. The initial rise in serum prolactin level was observed on the fourth day after pituitary transplantation, and then a higher serum prolactin level was maintained thereafter. Despite the higher prolactin level in the pituitary-grafted rat than in the control, no significant differences from the control in the weight of prostates and seminal vesicles and adrenal gland and the concentrations of serum luteinizing hormone (LH) and follicular stimulating hormone (FSH) were measured. This result showed that the weight of accessory sex organs was not affected by a higher serum prolactin within seven days.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of leuprolide on growth of rat prostatic tumor (R 3327) and weight of male accessory sex organs

Leuprolide, a synthetic LHRH analog, inhibited growth of the Dunning R 3327 androgen-sensitive rat prostatic tumor and induced weight loss in male accessory sex organs. The relationship between the mode of administration and efficiency of the treatment was examined. Maintenance of the drug level in vivo seemed to be one of the important factors in the suppression of tumor growth, while a decrease in the weight of the accessory sex organs was mainly dependent on the dose administered. No treatment with leuprolide surpassed the effect caused by castration. Cytosolic androgen receptor and acid phosphatase activity in the tumor tissues were not changed significantly after treatment with leuprolide.     

Effects of an LH-RH analogue in male rats pretreated with oestradiol benzoate.

Treatment of adult male rats with oestradiol benzoate (OB) for 21 days significantly decreased the body, testicular and accessory sex organ weights but increased anterior pituitary weight. OB treatment also significantly suppressed circulating FSH and LH levels as well as plasma and testicular concentrations of testosterone. The seminiferous tubules and interstitial cells were partly atrophied, and there was some effect on spermatogenesis, with step 14 to 19 spermatids being fewer than normal. Rats treated with OB for 21 days were then treated daily with LH-RH analogue ((D-Leu6, des-Gly-NH2(10))-LH-RH-ethylamide), to see if testicular function could be recovered. Circulating gonadotrophins were significantly elevated, testicular histology was normal and testicular and plasma testosterone concentrations and the accessory sex organ weights remained suppressed. These results suggest possible extra-pituitary effects of the LH-RH analogue, including a direct action on the testes and/or accessory sex organs.     

A quantitative study of serum testosterone,sex accessory organ growth,and the development of intermale aggression in the mouse

Radioimmunoassay of serum testosterone (T) was used to characterize circulating T levels in mice from birth to sexual maturity. Until 25 days of age, serum T levels ranged from 1 to 4 ng/ml. A significant increase in T concentrations was observed in 30-day-old males, followed by a secondary rise in serum T between Days 45 and 50 of life. The latter increment was associated with the appearance of extreme individual variation in circulating T levels which was also observed in adult (120 days) males. The most rapid growth of accessory sex organs occurred between 30 and 50 days of age, the period preceding attainment of peak serum-T levels. The first incidence of intermale aggression coincided with a prepubertal rise in circulating T, but adult levels of fighting were present prior to the secondary increase in T observed between 45 and 50 days of age. Although animals involved in a fight did not differ with respect to weight of the accessory sex organs or serum T concentrations, the male that weighed more than his opponent usually won an encounter. Compared to males in encounters in which no fighting occurred, animals that won or lost an aggressive encounter showed significantly greater accessory sex organ development. While circulating T is required for the initiation and maintenance of intermale aggression, it is apparent that additional factors are related to the onset of fighting and the establishment of dominance/ subordinance relationships in mice.     

Growth and reproductive development in the male tree shrew (Tupaia belangeri) from birth to sexual maturity

The growth and reproductive development of the male tree shrew were studied from birth to sexual maturity. An infantile phase from birth to Day 30 was characterized by the rapid involution of the testis and adrenal gland from a fetal condition followed by a nadir in testosterone levels and slow growth and differentiation of the testis and accessory sex organs. The initiation of puberty occurred collaterally with the emergence of the young from the nest and was marked by a sharp rise in testosterone levels from Days 30 to 35 to maximum levels at Days 40-55. Peak testosterone levels were temporally correlated with the onset of maximum growth and differentiation of the testis and accessory sex organs, descent of the testis, development of the scrotum, and a pronounced peak in the weight-velocity curve. The rapid growth of males at puberty contributed to a moderate degree of sexual dimorphism in this species. Puberty was attained at about Day 90 with the completion of spermatogenesis and the functional differentiation of the accessory sex organs. The postnatal development of the tree shrew conforms with the general primate pattern. The precise endocrine correlates established during puberty make Tupaia belangeri a useful small animal model for the study of puberty in primates.     

Effects of olive, corn, sesame or peanut oil on the body weights and reproductive organ weights of immature male and female rats.

Olive, corn, sesame or peanut oil which have been used as vehicles in the immature rat uterotrophic assay or Hershberger assay, for detection of endocrine disrupting effects of environmental chemicals, was administered to ten immature female rats by subcutaneous injection from postnatal day (PND) 21 for 3 or 7 days, and each oil was also administered to ten male rats from PND 21 for 7 and 10 days. The body weights, and the weights of sex and sex accessory organs in female and male rats were measured. There were no significant differences in body weights of female rats between each oil group and the control group, while the body weight of male rats in the group given peanut or olive oil was significantly increased from 8 or 9 days after administration. There were no changes in the sex and sex accessory organ weights of female or male rats related to the endocrine disrupters. The results of the body weights and organ weights demonstrate that each oil is a suitable vehicle for the immature rat uterotrophic assay. However, each oil is suggested to be unsuitable for the Hershberger assay, because the analysis of changes of sex accessory organ weights in this assay might be confused by the increased body weights.     

Pituitary-testicular axis abnormalities in immature male hypothyroid rats

The pituitary-testicular disturbances which follow the onset of hypothyroidism were studied in immature male Wistar rats rendered hypothyroid by treatment with methimazole (MMI) given in drinking water, starting at 40 days of age. Half of the animals continued on MMI (MMI group) up to 140 days of age; the remaining rats were withdrawn MMI at 100 days and injected thereafter s.c. with 3 micrograms of T3 daily, during the last 40 days (MMI + T3 group). Ten rats were used as controls (C group). Hypothyroidism induced in immature animals significantly decreased serum T4, T3, LH, PRL, and testosterone levels, and also impaired the normal growth of body and sex accessory glands. T3 replacement therapy helped to normalize serum hormonal levels, but the body and sex accessory gland weights were not fully corrected. Hypothyroidism also reduced the [125I]LH/hCG binding sites of testicular homogenates. T3 replacement was not able to improve the binding; nonetheless, the hormone-receptor affinity constant remained unaltered among the groups. Leydig cell responsiveness to hCG stimulation in vitro (0-82 nM) showed impaired testosterone production in the MMI group (25% of that found in the C group) and also in the MMI + T3 group (80% of that found in the C group). These data demonstrate that induction of hypothyroidism in the immature male rat leads to alterations in serum LH, PRL and testosterone levels, and suggest that thyroid hormones have a modulating action on the testis as far as LH-mediated testosterone secretion is concerned.     

The influence of aging on androgen dynamics in the male rat

Androgen assimilation was investigated in a variety of accessory sex organs (seminal vesicles and anterior, dorsal, lateral, and ventral prostates) and in several nonaccessory sex organs in male Wistar rats. After administration of a pulse dose of [³H]testosterone in vivo to intact young (3–4 months old) rats, [³H]testosterone was the primary radioactive steroid recovered from most organs examined, except for the secondary sex glands where the reduced metabolites, [³H]5α-dihydrotestosterone (DHT) and [³H]5α-androstanediol(s), predominated. At longer postinjection times, [³H]DHT was preferentially retained in the accessory sex glands, presumably reflecting intracellular metabolism of [³H]testosterone to this compound and subsequent specific binding of [³H]DHT to receptor proteins. At the longest postinjection interval investigated, the ventral prostate retained greater concentrations of [³H]DHT than the lateral prostate which in turn had a higher [³H]DHT concentration than the seminal vesicles or anterior or dorsal prostates. The latter three glands retained approximately equal concentrations of [³H]DHT. Scatchard plot analyses of cytosol binding in 24-h castrates indicated that with one exception, the level of high affinity DHT binding sites was generally correlated with the retention of [³H]DHT in vivo in intact rats. Specifically, while the affinity for DHT binding in all accessory sex organs was the same, the number of high affinity binding sites per mg wet tissue weight was on the order of ventral prostate > anterior prostate ≥ seminal vesicles ≥ dorsal prostate > lateral prostate. Studies of the influence of aging to 22–26 months revealed no apparent differences in the affinity of the DHT receptor for its ligand in any of the accessory sex glands from 24-h castrates when the receptors were present in levels sufficiently high to quantify. The concentration of available DHT receptors with advancing age remained constant in the anterior and dorsal prostates, increased in the seminal vesicles, and declined in the ventral and lateral prostates. The decreases observed in the ventral prostate were only partial, but the receptors of the lateral prostate declined to nondetectable levels.     

Testosterone and dihydrotestosterone levels in epididymis, vas deferens, seminal vesicle and preputial gland of mice after hCG injection

Temporal changes of testosterone (T) and dihydrotestosterone (DHT) levels were measured by RIA in epididymis, vas deferens, seminal vesicle and preputial gland of adult male mice after a single injection of hCG. The response of circulating T to hCG stimulation was rapid and persisted over a period of 48 h. The temporal changes of androgen content of target organs paralleled the modifications of circulating T. In all organs the high androgen levels attained at 1 or 4 h plateaued until 24 h, decreased thereafter and returned to basal values at 72 h. The concentration of T by sex accessory organs was more accelerated by hCG injection than its conversion into DHT.     

Effects of Castration on Growth and Reproduction of Helisoma duryi (Mollusca: Pulmonata)

Summary

Castration of Helisoma duryi disturbs the balance between growth and reproduction in favour of growth, as is evidenced by the stimulation of body and shell growth and reduction in egg mass production when compared with sham operated controls. Female accessory sex organ wet weight is increased in castrated and virgin snails. Male accessory sex organ wet weight is unaffected and female accessory sex organ wet weight is reduced by dorsal body ablation, suggesting that growth of differentiated female accessory sex organs is stimulated by the endocrine dorsal bodies. Albumen gland synthetic activity is inhibited in the absence of a functioning gonad. This inhibition may be due partly to the accumulation of secretory products within the glands and partly to the inactivation of the endocrine dorsal bodies and neurosecretory caudodorsal cells in the cerebral ganglia. The circulating levels of the vitellogenic protein ferritin are reduced by castration, and increased by injection and implantation of active gonadal tissue into castrates. This may be due to an indirect effect of gonadal factor (s) on the extragonadal synthesis of ferritin.     

Melatonin inhibition of pineal antigonadotrophic activity in male rats.

The influence of subcutaneous implants of melatonin on reproductive organ growth in neonatally testosterone propionate-(TP)-treated, blinded rats was investigated. The testes and accessory sex organs of rats that were TP-treated and blinded grew significantly slower than those of intact control rats. Either treatment of animals with melatonin or pinealectomy partially restored growth of the reproductive organs. In that the effects of melatonin treatment were similar to those of pinealectomy in this experiment model, it is speculated that melatonin may not be the principal pineal antigonadotrophic substance in the male rat.     

Imprinting of male sex tissues by neonatal endogenous androgens in mice. Molecular alterations following exposure to cyproterone acetate

This study was conducted to evaluate the growth and biochemical responsiveness of the epididymis, vas deferens and seminal vesicles of adult mice exposed to cyproterone acetate during the first 10 days of life. Results indicate that the weight and protein content of sex accessory organs were significantly depressed, testosterone and dihydrotestosterone concentrations were unaffected or increased, the number of cytosolic androgen-binding sites was slightly or significantly reduced. The efficiency of exogenous testosterone in promoting growth and protein synthesis in target organs of castrated adult males was significantly lowered by neonatal cyproterone acetate treatment. It is concluded that a deficient androgenic stimulation during neonatal life induces a limited response of sex target organs to endogenous or exogenous androgens in adulthood.     

Seasonal changes in circulating testosterone and androstenedione concentration and their correlation with the anomalous reproductive pattern in the male indian sheath-tailed bat, Taphozous longimanus

The relationship between reproductive organs, circulating testosterone, and androstenedione concentration in the male sheath-tailed bat, Taphozous longimanus, was studied. The masses of testis, accessory sex gland (prostate, ampullary), and epididymides showed three peaks, one each in October, January, and April. Monthly changes in testosterone also peaked during October, January, and April and closely coincided with the peak spermatogenesis. Serum androstenedione concentration peaked during November and January. Testosterone showed a strong correlation with masses of testis and accessory sex glands, while androstenedione showed strong correlation with the body mass. Different threshold levels of testosterone may be required to trigger spermatogenesis, secretory activity of accessory sex glands and mating in Taphozous longimanus and may be responsible for reproductive asynchrony in this species. Higher circulating concentrations of testosterone and androstenedione throughout the year in this species, as compared with other mammalian species, may be responsible for prolonged retention of sperm in the epididymides.     

Testosterone concentration in testicular venous blood of adult rats and seminal citric acid and fructose concentration as well as weight of accessory sex organs.

In 31 adult rats of Wistar strain (body weight 231 +/- 14g) the relationships between testosterone concentration in testicular venous blood of an individual rat and weight of accessory sex organs (testes, seminal vesicles, ventral prostate, levator ani muscle) and citric acid and fructose concentrations in seminal vesicles were investigated. No direct relationship was found between testosterone concentration and the above parameters. The correlation coefficient varied from 0.042 to 0.394.     

日龄和交配状态对亚洲玉米螟雄蛾内生殖器特征的影响

【目的】揭示日龄和交配对亚洲玉米螟Ostrinia furnacalis雄蛾内生殖器官的影响,以及亚洲玉米螟雄蛾的交配状态和性信息素诱捕之间的关系。【方法】采用行为学和生殖器解剖技术,研究不同日龄和交配状态亚洲玉米螟雄蛾内生殖器特征,并将其与田间性信息素诱捕雄蛾进行比较。【结果】除了精巢、输精管、储精囊、附腺、复射精管和单射精管外,亚洲玉米螟雄蛾内生殖系统还包含1对附腺囊,同时单射精管非角质化区分为5段(PS1-5),PS1又细分为5区(PS1Ⅰ-Ⅴ)。生殖器内含物可分为5级(0-4级),存在充满和未充满生殖器两种状态。1日龄雄蛾内生殖系统不同器官的内含物等级存在差异,但是日龄对雄蛾生殖系统内含物等级无明显影响。交配后0 h亚洲玉米螟雄蛾,除输精管、储精囊和附腺囊外,其余生殖器官内含物等级较未交配雄蛾的均发生显著变化。随着交配后时间的增加,雄蛾生殖器内含物等级逐渐恢复,各器官内含物等级恢复的速度存在差异,交配后60 h所有内含物等级均恢复到未交配状态。但是直到交配后228 h,交配雄蛾PS5内含物仍然表现出断裂等形态特征,和未交配雄蛾存在差异。性信息素引诱雄蛾中有60.9%的生殖系统表...     

Seasonal timing of sperm production in roe deer: interrelationship among changes in ejaculate parameters,morphology and function of testis and accessory glands

Roe deer are seasonal breeders with a short rutting season from mid-July to mid-August. The seasonality of reproductive activity in males is associated with cyclic changes between growth and involution of both testes and the accessory sex glands. This study characterizes morphological and functional parameters of these organs prior to, during and after breeding season in live adult roe deer bucks. Size and morphology of the reproductive tract was monitored monthly by transcutaneous (testes, epididymis) and transrectal (accessory glands) ultrasonography. Semen was collected by electroejaculation. Concentration, motility and morphological integrity of spermatozoa as well as the content of proteins and testosterone in semen plasma were evaluated. Proportions of haploid, diploid and tetraploid cells were estimated by flow cytometry in testicular tissue biopsies. Serum testosterone was measured by enzyme immunoassay. Most parts of the male reproductive tract showed distinct circannual changes in size and texture. These changes were most pronounced in the testes, seminal vesicles, and prostate. All reproductive organs were highly developed during the rut only. The volume of ejaculates, total sperm number and percentages of motile and intact spermatozoa also showed a maximum during this period and corresponded with high proportions of haploid cells in the testis. The highest percentages of tetraploid cells were found in the prerutting period. The production of motile and intact spermatozoa correlated with both the protein content of semen plasma and the concentration of testosterone in semen plasma and blood serum. These results suggest the importance of combined actions of the testes and accessory sex glands and the crucial role of testosterone in facilitating the optimal timing of intensified semen production to ensure sufficient numbers of normal spermatozoa in seasonal breeders.