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PubMed1980

Surface pits of typical gonadotrophs and castration cells of the rat anterior pituitary suggestive of exocytosis and micropinocytosis.

For a long time, the occurrence of exocytotic discharge of secretory granules from the typical gonadotrophs (Type 1 gonadotrophs) of the anterior pituitary has been doubted. A simple observation with immunocytochemistry and morphometric examination using transmission electron microscopes indicated an increase in number of surface pits and subsurface vesicles of the typical gonadotrophs after castration, which were confirmed by immunocytochemical reaction with anti-LH beta. Large pits and vesicles were also increased progressively as days after castration advanced. Some large pits contained dense granules or less dense flocculent substance. These findings suggest that the typical gonadotrophs also exert granule discharge by the mechanism of exocytosis and concomitant retrieval of surface plasma membrane by the micropinocytosis.

Animals↗
PubMed1983

Effects of unilateral castration and unilateral cryptorchidism of the Holstein bull on plasma gonadotropins, testosterone and testis anatomy.

The effects of unilateral castration (UC) and induced unilateral cryptorchidism (CR) on plasma hormones and testis anatomy were studied in 36 Holstein bulls altered at either 3, 6 or 9 mo of age (n = 12). Plasma hormone concentrations were determined in six samples collected at hourly intervals on d 0, 1, 3, 7, 14 and 30, and then at monthly intervals through 6 mo after gonadal manipulation. Although plasma testosterone (T) showed a transient decrease (P less than .05) immediately after treatment, mean plasma concentrations of luteinizing hormone (LH) and T were unaffected by UC or CR over the 6-mo period (P greater than .05). Both hormones increased (P less than .05) in concentration with advancing age. Plasma follicle stimulating hormone (FSH) concentration was greater (P less than .05) in UC than in intact (IN) bulls overall, while FSH in CR bulls did not differ (P greater than .05) from either group. At slaughter, 11 mo after gonadal alteration, mean testis weight, ratio of testis weight to body weight and mean testis sperm cell numbers were increased (P less than .05) in UC bulls compared with mean testis values in intact (IN) bulls. Unilateral castration increased (P less than .05) seminiferous tubuler diameter and seminiferous epithelial cell height from basement membrane to the border of the lumen, but did not alter the ratio of tubuler to interstitial space within the testis. Seminiferous tubuler diameter and epithelial cell height were increased (P less than .05) in CR compared with IN bulls. Unilateral gonadal alteration at 3 mo of age caused a greater (P less than .05) hypertrophy of the scrotal testis in both UC and CR bulls than alteration at 6 or 9 mo of age. Results indicate that unilateral gonadal disruption is followed by rapid compensation in testis T production, little change in systemic LH and a rapid increase in secretion of FSH in the bull within those ages investigated. Further, UC elicits a greater compensatory hypertrophy than CR and the pituitary-testis endocrine axis is more responsive to alteration at 3 mo than at 6 or 9 mo of age in the bull.

Animals↗
PubMed1979

Effect of cyproterone acetate on adrenal cortex of castrated mice.

Castrated adult male C57BL/6J mice displayed a wide perimedullary zone (secondary X-zone) whose cells were characterized by proliferated rough and smooth endoplasmic reticulum and elongated mitochondria with lamellar cristae. Castrated mice which received 0.08 mg/g of cyproterone acetate showed a much inhibited secondary X-zone at the light microscopic level, while at the ultrastructural level the perimedullary cells lacked the proliferated rough and smooth endoplasmic reticulum as well as the elongated mitochondria. Cyproterone acetate may inhibit the steroidogenic parameters of the androgen-producing cell population of the adrenal cortex without testicular mediation.

Adrenal Cortex↗
PubMed1976

The half-life of luteinizing hormone in intact and castrated quail during photoperiodic stimulation.

In the Japanese quail (Coturnix coturnix japonica) the plasma concentration of luteinizing hormone (LH) depends on the physiological state of the animal. Low levels are found in sexually immature birds on short days (0.8 +/- 0.1 (n = 20) ng/ml) while after exposure to long days, sexually mature birds have a significantly higher LH level (4.4 +/- 0.4 (n = 20) ng/ml). Castration of long day males results in an even higher rise in LH concentration to 16.8 +/- 1.8 (n = 16) ng/ml. When the half-life (t1/2) of circulating LH was determined it was found to have two components: a fast t 1/2 of about 6 min and a slower component of either 20 min (determined by a radioisotope method), or 40 min (following hypophysectomy). No significant difference was observed in either of these components between birds in the three physiological states (short days, long days, castration plus long days). It would appear, therefore, that since the half-life of plasma LH remains constant, the difference in circulating LH observed under the various physiological conditions results solely from a change in the rate of LH secretion.

Animals↗
PubMed1980

Effect of testosterone on the androgen receptor in the liver cytosol and nuclei of castrated male rats.

The androgen-binding sites in the cytosol and nuclei were decreased 1 week following castration and this reduced level was sustained for 2 weeks. A maximal increase of the androgen-binding sites in the cytosol was induced by a single injection of testosterone, while the sites in the nuclei were increased gradually with the duration of testosterone injection. These findings suggest that testosterone was able to induce the binding sites in the liver cytosol and nuclei which had been reduced after castration.

Animals↗
PubMed1995

The effect of neonatal exposure to diethylstilbestrol, coumestrol, and beta-sitosterol on pituitary responsiveness and sexually dimorphic nucleus volume in the castrated adult rat.

The neonatal hormone environment influences the sexually differentiated patterns of development. Estrogens, derived from intracerebral aromatization, promote male pattern development of the central nervous system. The purpose of this study was to determine the effects of neonatal exposure to environmental estrogens on luteinizing hormone (LH) secretion and development of the sexually dimorphic nucleus of the medial preoptic area (SDN-POA) in castrated adult rats. Neonatal rats of both sexes received injections of either corn oil, 0.1 microgram diethylstilbestrol (DES), 3 micrograms beta-sitosterol (B1), 30 micrograms beta-sitosterol (B2), 0.1 microgram coumestrol (C1), 1 microgram coumestrol (C2), or 10 micrograms coumestrol (C3) on Day 1-10 of life and were castrated on Day 21. Right heart catheters were placed on Day 42, and GnRH (50 ng/kg) was administered. Blood was sampled for LH at 0-, 5-, 10-, 15-, and 30-min intervals. All doses of beta-sitosterol and coumestrol elicited increased basal levels of LH in females. In males, B1, B2, C2, and C3 increased basal levels of LH. The GnRH-induced LH increase was prevented in females treated with diethylstilbestrol and 10 micrograms of coumestrol. Males in all treatment groups exhibited GnRH-induced LH surges. The animals were sacrificed by decapitation on Day 49. Volumes of the SDN-POA of the groups were compared. Treatment with the agents did not result in significantly increased SDN volume in females; nor was there a difference in SDN size among the male groups. These data show that exposure to environmental estrogens early in development alters both postpubertal pituitary response to GnRH and basal LH secretion in females and alters only basal LH secretion in males. No significant enlargement (i.e., masculinization) of the SDN-POA was exhibited.

Animals↗
PubMed1976

[Study of the hypothalamus of neonatally castrated rats by the karyometric method].

The sensitivity of different hypothalamic regions to the effect of androgens has been studied during the period of the brain sex differentiation. The castration of animals during the first week of life was shown to result in the marked increase of size of the neuron nuclei in the preoptic, suprachiasmatic, arcuate and ventromedial nuclei of the hypothalamus; the size of neuron nuclei in the dorsomedial nucleus suffered no changes. The dynamics of size of the cell nuclei was followed in different hypothalamic regions with respect to the time of castration.

Animals↗
PubMed1975

[Bone calcium metabolism following local x-irradiation. XIII. Effect of castration and estrogens on the general response of male rats].

The course of local and general deviations in osseous tissue of locally irradiated male white rats is different in hormonally not influenced and in castrated animals. By castration, both the intensity and the variations of this response are inhibited whereas especially the second osseous tissue shows a great deal more sensitivity. The male sex hormones thus lead to a certain instability and intensity of the defence reactions against local radiation damage which derail more easily than in females.

Age Factors↗
PubMed1975

[Metabolism of calcium in bones following local x-irradiation. 14. Effect of castration and estrogens on the general response].

The female sex hormones cause a moderation of the local and general metabolic response to local irradiation of an extremity in female white rats. After castration in adult age, therefore, a more intense reaction is observed with more distinctly marked changes of the 45Ca-incorporation. In male rats, consequently, there is a more vivid course of general response. In these, castration contrarily brings about a moderation of the general response.

Age Factors↗
PubMed1975

Histochemically demonstrable changes in amylase activity in submaxillary salivary glands of puberal male mice following castration.

The sexual dimorphism in mouse submaxillary glands is well documented. The main difference is seen in the granular convoluted tubules (G.C.T.) which in the adult male are large and in the adult female are small and fewer. Previous studies have shown that amylase is localized histochemically to these G.C.T.'s; that following castration there is a histological reduction in size and number of the G.C.T.'s and a roughly 50 per cent decrease in amylase activity demonstrable biochemically. In the present study 74 male mice aged 60 days were divided in six groups. The animals were fasted overnight. Under general anaesthesia, the submaxillary glands on the left side were removed and frozen in liquid nitrogen for subsequent histochemistry. The animals were then castrated and returned to their cages. At periods of 2, 4, 6, 8, 10 and 12 weeks later, the other submaxillary gland was removed under the same conditions, and the animals were then killed. Fresh frozen cryostat sections of both glands were subjected to the starch substrate film technique for the histochemical demonstration of amylase. Adjacent sections were stained with HE. The 2-week animals showed a slight but define reduction in size and number of G.C.T.'s and a parallel reduction in amylase activity. This was more pronounced by 4 and 6 weeks. In the 4-week animals, however, the changes were not consistent, being more pronounced in some animals than in others. This same phenomenon was observed in the 6-, 8- and 10-week animals, in some of whom there was considerable G.C.T. atrophy in the submaxillaries and in others very much less. In many of the 12-week animals there was very little evidence of G.C.T. atrophy. These findings confirmed other studies which suggested that there may be some regeneration of G.C.T's, possibly as a result of influence of other endocrine glands such as thyroid, adrenal and pituitary.

Amylases↗
PubMed1975

[Serum FSH and LH levels in women following surgical castration and during hormonal management of menopause symptoms].

Using the radioimmunological method, FSH and LH levels were determined in women immediately after surgical castration and after an elapse of 18 months to two years. A twofold increase in FSH was found already two days after castration, while an increase in LH only after six days. Increased FSH and LH levels were observed as late as after two years when upon the administraion of estrogens and androgens, the feed-back mechanism of the pituitary still plays a role. In women with pronounced menopausal disturbances the FSH and LH levels were followed up after the application of Folivirin and Agofollin-Depot over a period of two weeks. There was a constant decrease in FSH of all women immediately after the injection, while the responses in LH were subject to variation, the decreased LH levels being found in all the women only towards the end of the second week. Folivirin was found more suitable for mastering the menopausal disturbances.

Adnexa Uteri↗
PubMed1975

Characteristics of the hypothalamic and hypophyseal cytoplasmic estradiol binding substances. Effects of neontaal castration and testosterone administration.

Some physicochemical characteristics and binding capacities of the cytoplasmic estradiol-receptor complexes of the rat hypophysis and hypothalamus, were determined in intact males and females, neonatal castrated males and neonatal and adult testosterone injected females. By gel filtration and density gradient centrifugation the hormone receptor complexes obtained in vitro, shared the same properties in both tissues. The hydrodynamic radius was estimated to be 60 A, The sedimentation coefficient 8.5 S, the frictional coefficient f/fo was 1.42 corresponding to axial ratio (prolate) of 7.85. The molecular weight was 263 000. The data suggest a highly asymmetric molecule similar to the uterine soluble estradiol-receptor complex. No differences were observed in the hypothalamic binding capacities of diestrous females and adult males. The results expressed as fmol of hormone bound/mg cytoplasmic protein were 2.40 +/- 0.32 and 2.54 +/- 0.26, respectively. For estrous females it was 3.72 +/- 0.44. Neonatal castration or testosterone administration increased significantly the binding activity in adulthood. Adult females treated with testosterone showed the lowest level of the hypothalamic estradiol receptors (1.41 +/- 0.56). No differences were observed in the in vitro titration of the pituitary cytoplasmic estrogen binding sites.

Animals↗
PubMed1975

[The effect of castration on the mast cells of the ventral gland of male gerbils (Meriones unguiculatus, Gerbillidae)].

The number of labrocytes increases in male gerbil ventral gland connective tissue, as castration makes epithelial structures enter a resting stage. Inversely, labrocytes number decreases when testosterone injection to castrate males initiates epithelial activity. These variations of mast cells number are not a consequence of changes in gland volume, which only act upon epithelial tissues and do not modify "connective tissue compartment".

Animals↗
PubMed1992

Effects of prolactin and androgens on enzymes of carbohydrate metabolism in prostate of castrated bonnet monkeys Macaca radiata (Geoffroy).

Effects of prolactin (PRL), bromocriptine (Br), testosterone propionate (TP), dihydrotestosterone (DHT) and the combinations of these androgens with PRL/Br on the specific activities of caudal and cranial prostatic cellular enzymes involved in carbohydrate metabolism in castrated mature bonnet monkeys have been studied. Castration decreased all the enzymes studied such as hexokinase (HK), 6-phosphofructokinase (6-PFK), glyceraldehyde-3-phosphate dehydrogenase (G-3-PD), pyruvate kinase (PK), glucose-6-phosphate dehydrogenase (G-6-PD) and 6-phosphogluconate dehydrogenase (6-PGD) in the cranial and caudal prostates. PRL elevated the activities of all the enzymes above normal except G-3-PD of cranial lobe. In the caudal lobe, PRL brought back the activities of HK, PFK, PK, G-6-PD to normal and 6-PGD above normal except G-3-PD. TP/DHT treatment increased all the enzymes in both the lobes. PRL given along with TP/DHT further enhanced the androgen action with regard to HK, PK, G-6-PD and 6-PGD of cranial and PFK, G-3-PD, PK, G-6-PD and 6-PGD of caudal lobe. Br treatment did not produce any alteration of these enzymes in both the lobes. In the cranial lobe, during Br+TP/DHT treatment, the stimulating effects of androgen were unaffected on all the enzymes except PK. On the other hand in the caudal, the stimulatory effects of androgens were affected and the activities of HK, PFK, PK and 6-PGD were significantly decreased. The present results suggest that PRL has a direct as well as a synergistic action with androgens on enzymes of EMP and HMP shunt in the prostates of monkeys.

Androgens↗
PubMed1976

[The effect of urine from castrated male or female guinea pigs and rats on the estrous cycle of guinea pigs and rats, respectively].

A 24-hour reduced cycle duration was observed in 5-day cyclic female rats exposed to the odor of urine from male or female castrated rats. A decrease in the duration of the period of vaginal closure, ranging from 2 to 5 days, was observed in female guinea pigs exposed to the odor of urine from male or female castrated guinea pigs. The pheromonal activity of urine in both species was concluded to be no dependent upon the gonadal function.

Animals↗
PubMed1977

[Localization of a 5alpha-reductase activity in the nuclear membranes of the anterior hypophysis of normal and castrated adult male rats].

A 5alpha-reductase activity may be found in purified nuclei from anterior pituitary of intact or castrated male rats. When nuclear membranes are separated from nucleoplams this enzymic activity is recovered in nuclear membranes. Following 7 days of castration, the 5alpha-reductase activity in nuclear membranes is increased by 105 % with regard to the activity in nuclear membranes from intact animals.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗