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PubMed1975

Morphometric evaluation of sebaceous gland volume in intact, castrated, and testosterone-treated rats.

Starting a 19 weeks of age six male rats, castrated at 16 weeks, were injected intramuscularly three times per week with 0.25 mg testosterone propionate (dissolved in sesame oil) per 100 grams body weight. Four castrated control rats received sesame oil only. Samples of dorsal skin were taken under light ether anesthesia at the time of orchidectomy and at weekly intervals during treatment. Histologic sections were cut perpendicular to the skin surface, stained with hematoxylin and eosin, and analyzed morphometrically for their volume content of sebaceous glands, A square grid of 42 sampling points was superimposed on each microscopic field at a maganification of 300X and an average of about 1000 points were counted over the entire thickness of the skin in each section. The average thickness of the skin was also determined for each sample. Three weeks after castration the mm-3 of sebaceous glands per cm-2 of skin was reduced from 1.76 to 0.96, a difference that is statistically significant at p is less than 0.005. One week after starting testosterone injections, the volume of sebaceous glands was more than double that in the control animals: 3.0 vs 1.2(p is less than 0.02). Even greater differences were found at 2 to 4 weeks of treatment.

Animals↗

PubMed1979

The effect of clomiphene on uncastrated and castrated male transsexuals.

Clomiphene was administered at a daily dose of 100 mg for 5 consecutive days to two groups of male subjects. There were three uncastrated male transsexuals (Group A) and nine castrated male transsexuals (Group B). In the uncastrated subjects Clomiphene enhanced the secretion of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone (T) starting from day 3 of treatment. The magnitude of the increment ranged from 150%--250% over the mean basal plasma level for LH, 113%--262% for FSH and 12%--68% for T. In contrast, Clomiphene suppressed both FSH and LH in the castrated subjects. Equal suppression of both the gonadotrophins were observed. The levels of FSH and LH in plasma on day 3 were suppressed to 66.4% and 66.2% of their respective mean basal levels. Two days after the termination of treatment, suppressions were maintained. These results suggest that Clomiphene acts as an anti-oestrogen in uncastrated male transsexuals and in castrated male transsexuals who have subphysiological levels of oestradiol it acts as a weak oestrogen.

Adult↗

PubMed1981

Recovery of hypophyseal-testicular function from sex steroid treatment and the pituitary response to castration in male transsexuals.

Twenty-one male transsexuals who had been on steroid hormone therapy for at least 1 year volunteered for this investigation. Their hormone profiles after stopping sex steroid hormone treatment for periods ranging from 2 to 70 days were examined. Based on their testosterone levels before the sex-reassignment operation which includes castration, penectomy and the construction of an artificial vagina, two separate groups can be distinguished; those with low (group A) and the other with normal (group B) levels. The gonadotrophins levels in group A and group B were (respectively) significantly (P less than 0.05) lower and higher than corresponding levels in a group of normal males. Castration had caused elevations of FSH and LH in both groups. Although the increment rates were different, both groups attained the same maximum levels of FSH and LH. Within each group, the patterns of FSH and LH responses to castration were similar. However, differences in rates and time of significant elevation of FSH and LH were noted. These observations indicate that there is a delay between the cessation of steroid treatment and the recovery of testicular and hypophyseal functions. Testicular function seems to be altered by steroid treatment since excessive secretions of FSH and LH are needed to produce normal testosterone levels. The secretions of FSH and LH are controlled in some ways by the same mechanisms, while they, in other respects, are controlled by different factors.

Castration↗

PubMed1981

Effects of castration, sex steroids, LHRH and glucocorticoids on LHRH binding in the anterior pituitary of male rats.

In the present study we have examined the effects of gonadotrophin releasing hormone (LHRH), sex steroids and glucocorticoids on the binding of LHRH to receptors in the pituitary of male intact and castrated rats. In intact rats, LHRH (10 microgram/day) treatment for 11 days caused a significant increase in LHRH binding, whereas testosterone (500 microgram/day) or oestradiol (50 microgram/day) were inhibitory. 17-hydroxyprogesterone and dexamethasone were without effects. In castrated rats, LHRH caused a marginal decrease in LHRH binding. Much greater inhibition was observed with testosterone and oestradiol. 17-hydroxyprogesterone reduced binding to that of intact controls, whereas dexamethasone was ineffective. When different doses of sex steroids were tested, both oestradiol, testosterone and 5 alpha-dihydrotestosterone inhibited LHRH in a dose-dependent manner. The lowest doses of steroids causing significant inhibition of LHRH binding in castrated animals were 0.5, 50 and 500 microgram/day for oestradiol, 5 alpha-dihydrotestosterone and testosterone, respectively. The present study shows that pituitary receptors for LHRH are regulated both by sex steroids and LHRH itself.

Animals↗

PubMed1984

Pharmacokinetics of sulfamethazine in male, female and castrated male swine.

The concentration of sulfamethazine in plasma and sulfamethazine and its metabolites in urine were compared in male, female and castrated male swine. A surgical technique for placement of catheters in the urinary bladder was used to facilitate the collection of urine in males and castrated males. The elimination rate of sulfamethazine from plasma and the excretion of parent drug and metabolites into urine did not differ significantly among females, males and castrated male swine.

Animals↗

PubMedDate not supplied

The effects of castration on the subependymal plate of the rat.

Earlier studies have shown that glial tumours, produced by the intracerebral implantation of chemical carcinogens, originate from the subependymal plate. In the present study the effects of castration on cell number and proliferation in the subependymal region has been investigated as such treatment has been shown to reduce the incidence of gliomata produced by an implanted carcinogen. An age-related reduction in mitotic activity and nuclear density was found in the subependymal plate. Castration produced a consistent reduction in mitotic activity but the nuclear density was unchanged. The results suggest that the reduction in tumour incidence produced by castration cannot be explained simply on the basis of reduced proliferation in the population believed to be at risk and that other, as yet, undefined factors must be involved. In addition, it appeared that there was also no simple relationship between brain growth and cell proliferation in the subependymal plate.

Animals↗

PubMed1974

Lack of copulatory behaviour in male castrated rats after p-chlorophenylalanine.

1 The effect of p-chlorophenylalanine (PCPA) on the copulatory behaviour of normal and castrated male rats with females in oestrus was studied.2 Castration 2 months before the experiment completely prevented the increased copulatory behaviour produced by PCPA in normal rats.3 The administration of testosterone restored the copulatory behaviour in the castrated rats indicating that testosterone is essential for this behaviour.

Animals↗

PubMed1985

Secretory cell activity in the hamster seminal vesicle following castration. A morphometric ultrastructural study.

The ultrastructure of hamster seminal vesicle epithelium was studied 7, 14, 21 and 28 days after castration using a stereological approach. The results show that castration promotes epithelial reorganization, mainly characterized by reduced epithelial cell size and number, decreased rough endoplasmic reticulum and Golgi complex, increased lysosomes and lipid droplets, increased apical secretory granule size and number, and increased intracellular secretory products per average epithelial cell. It is concluded that after testosterone withdrawal the secretory activity of hamster seminal vesicle epithelial cells, although reduced, is not abolished, and that exocytosis is relatively more reduced than secretory protein production. We suggest that an extracellular androgen source is responsible for secretory activity not being lost in the epithelial cells of castrated hamster seminal vesicle.

Animals↗

PubMed1982

Effect of castration on medial preoptic/anterior hypothalamic neurone responses to stimulation of the fimbria in the rat.

1. Single unit extracellular recordings were made from medial preoptic/anterior hypothalamic neurones in response to electrical stimulation of the ipsilateral fimbria. The effects of castration on neuronal responses were investigated and the pathway of the fimbria input analysed using multiple stimulation and selective lesions. The percentage of responsive medial preoptic/anterior hypothalamic neurones which had connexions with the medial forebrain bundle was also investigated.2. Orthodromic action potentials were recorded from 192 medial preoptic/anterior hypothalamic neurones in twenty animals (ten gonadally intact and ten castrated). These neurones responded to a single shock stimulus applied to the ipsilateral fimbria by producing one or one to three action potentials followed by an inhibitory period (similar to simple and complex spikes found in hippocampus and cerebellum). A further forty-eight neurones showed a post-stimulus inhibition. Castration significantly reduced the percentage of medial preoptic/anterior hypothalamic neurones that responded reliably to 0.6 Hz stimulation, lengthened the inhibitory periods, reduced the percentage of neurones producing one to three action potentials and lengthened their interspike intervals.3. Further experiments using ten animals showed that medial preoptic/anterior hypothalamic neurones orthodromically stimulated from the fimbria were also driven by stimulation of the ipsilateral stria terminalis and the cortico-medial and basolateral amygdala. Lesioning the stria terminalis abolished the responses of medial preoptic/anterior hypothalamic neurones to stimulation of the fimbria.4. In five animals the responses of fifty-seven medial preoptic/anterior hypothalamic neurones orthodromically stimulated from the fimbria were recorded after stimulation of the medial forebrain bundle. 44.5% of these neurones were stimulated antidromically and 25.6% orthodromically from the medial forebrain bundle. Neurones responding to fimbria stimulation by producing one to three action potentials were more likely to have connexions with the medial forebrain bundle.5. The relevance of these findings to local neuronal circuitry and the control of sexual behaviour are discussed.

Afferent Pathways↗

PubMed1977

Dominant-subordinate relationships in castrated male mice bearing testosterone implants.

This study tested the hypothesis that subordination in male mice is directly related to reduced levels of circulating testosterone. Several measures of aggressiveness and submissiveness were quantified during or after daily encounters between pairs of intact males, castrated males, or castrated males bearing testosterone implants that were designed to maintain plasma testosterone titers at levels slightly above those of intact males. Behavioral measures included the total amount of fighting that resulted from daily pairing, the tendency for subordinates to fight back, and the relative frequency of urine marking. In all these regards, pairs of testosterone-implanted, castrated males formed dominant-subordinate relationships that involved apparently normal submissive behavior (compared to intact control pairs). Thus we found no evidence that submissive behavior was directly related to a reduction in circulating testosterone titers.

Animals↗

PubMed1997

Short- and long-term effects of testosterone on diaphragm in castrated and normal male rats.

The effects of short- and long-term testosterone absence or treatment on the diaphragm were studied in castrated and sexually normal male rats. Compared with control rats (untreated normal males), testosterone absence or treatment did not significantly affect costal weight. In untreated castrated males, there were significant decreases in specific forces, type II fiber cross-sectional area, and myosin heavy chain (MHC) isoform 2B after 2.5 wk. In castrated males that received testosterone, there were significant increases in specific forces, type II total fiber proportional area, and relative expression of all adult diaphragm fast MHC isoforms (MHC-2all) after 2.5 wk. In normal males that received testosterone, the only significant finding was an increase in MHC-2B after 2.5 wk. Across all groups, there was close correlation between increases in maximum tetanic forces and MHC-2all. Changes in diaphragm function and composition were closely related to changes in serum testosterone levels at 2.5 wk. The lack of significant change in diaphragm function at 10 wk occurred despite changes in serum testosterone levels and diaphragm composition similar to those at 2.5 wk. These findings support our hypothesis that the effects of testosterone are dependent on basal circulating androgen levels and study duration.

Animals↗

PubMed1980

Photoperiod-induced change in responsiveness of the hypothalamic-pituitary axis to exogenous 5 alpha-dihydrotestosterone and 17 beta-estradiol in castrated male hamsters.

Exposure to short day lengths for 9 weeks renders the hypothalamic-putuitary axis of the castrate hamster extremely responsive to the negative feedback effect of exogenous testosterone. The systemic and/or local conversion of testosterone to 5 alpha-dihydrotestosterone (5 alpha-DHT) or 17 beta-estradiol (E2) is considered to be an important step in its action on target tissues. The present study was designed to determine if the photoperiod can induce changes in the sensitivity of the hypothalamic-pituitary axis to the inhibitory effects of 5 alpha-DHT or E2. 5 alpha-DHT-filled Silastic capsules that were 2, 4, or 8 mm long greatly reduced serum LH and FSH levels in castrates that were exposed to a nonstimulatory LD 8:16 light cycle, but not in animals exposed to a stimulatory LD 14:10 light cycle. E2 capsules that were 1, 2, 4, or 8 mm long greatly reduced serum LH and FSH levels in castrates exposed to LD 8:16, but not in animals exposed to LD 14:10. Serum gonadotropin levels were reduced in all of the animals receiving the larger 5 alpha-DHT (20 or 50 mm long) or E2 (20 mm long) capsules, irrespective of photoperiod. Thus, the photoperiod can alter the sensitivity of the gonadotropin control center to the negative feedback effect of both the 5 alpha-reduced derivative of testosterone, 5 alpha-DHT, and the aromatized metabolite of testosterone, E2. These results suggest that testicular secretions besides testosterone and/or extratesticular conversion of testosterone to its metabolites may be involved in the photoperiodic inhibition of the hamster reproductive system.

Animals↗

PubMed1987

Topographic organization of the karyometric response to neonatal castration of the male mouse in the paraventricular and ventromedial hypothalamic nuclei.

We have analysed the karyometric development of four topographic subdivisions of the paraventricular nucleus (rostral, medial, lateral and caudal) and three topographic subdivisions of the ventromedial nucleus (ventral, central and dorsal) of the hypothalamus in neonatally castrated male mice. Castration at birth produces a decrease of the nuclear sizes from the 10th to the 35th postnatal day, but after this age, no differences were detected in comparison with the sizes of the control male mice. Neonatal gonadal hormone deprivation also produces changes in the nuclear shape of the nuclei, that tend to be more spherical in both centres, as we could establish after the study of the form factor parameter (perimeter/area ratio). We have found differences in the response of both hypothalamic nuclei to neonatal castration and differences in the response of the topographic subdivisions of both of them.

Animals↗

PubMed1991

Morphological study of the development of the disseminate prostate in intact and castrated male pigs aged two to six months.

The light-microscopical and ultrastructural differentiation of the disseminate prostate was studied in 12 boars and 8 barrows, ranging in age from 8 to 28 and 12 to 27 weeks, respectively. The barrows had been castrated at the age of 8 weeks. In young boars the prostate is organized in an inner zone and an outer zone. The glandular tubules of the latter are more differentiated than those in the inner zone. Sexual maturation in the prostate is characterized by almost complete reduction of the inner zone and concomitant enlargement of the outer zone. This differentiation of the inner zone occurs progressively and is manifested by a higher density of the glandular tubules, by a decrease in the number of basal cells and by an increase in the secretory tubular cells containing more microvilli, organelles and secretory vesicles. A few weeks after castration, the characteristic morphology of the undifferentiated inner zone is found throughout the entire glandular layer. The number of glandular tubules in barrows has decreased, and their cells show minimal secretory activity, nuclear indentations and a decrease in their organelles. A further castration effect is vacuolization of the perinuclear cytoplasm in numerous glandular cells.

Animals↗

PubMed1975

Impaired 3H-testosterone uptake and metabolism in the accessory sex glands of diabetic castrated male rats.

The uptake and retention of 1,2-3H-testosterone in accessory sex glands, muscle and liver of streptozotocin diabetic castrated male rats, insulin-treated diabetic castrated rats and non-diabetic castrated control rats were studied at various time intervals after an intravenous injection. Diabetes reduced the retention of 3H-testosterone in the prostate, the preputial gland and the epididymis. Exogenous insulin slightly increased the retention of 3H-testosterone in these tissues of diabetic rats. No significant differences in the radioactivity in the rectus abdominis muscle, the coagulating glands and the seminal vesicles were found between the various experimental groups. Ventral prostate homogenates obtained from diabetic and control rats were incubated with 3H-testosterone in vitro. The steroids were extracted and thin-layer chromatographs were scanned for radioactivity. In prostatic homogenates taken from diabetic rats, testosterone transformation to dihydrotestosterone was reduced. The results indicate that the impaired function and androgen retention of the accessory sex glands of diabetic male rats is at least partly due to the reduced formation of dihydrotestosterone from testosterone.

Animals↗

PubMed1987

Effects of cyproterone acetate on mating behavior, testicular morphology, testosterone level, and body temperature in male ferrets in comparison with normal and castrated males.

Effects of surgical castration of 60-day-old male ferrets are compared with the effects of a chemical castration with cyproterone acetate from postnatal day 60 until 360. Investigations were made on mating behavior, intermale aggression, testicular morphology, plasma testosterone level and body temperature. While controls show seasonal variations in all parameters, according to the annual cycle of sexual activity and inactivity, both, surgically and chemically castrated ferrets show throughout the year constant parameters similar to that of controls during the sexual inactive period. All investigated effects of a long-term treatment with cyproterone acetate are fully reversible within 2 years after termination of drug administration.

Animals↗

PubMed1997

Operations on hermaphrodites and castration in Byzantine times (324-1453 AD).

The authors present and comment on the surgical methods performed on hermaphrodites and for castration, which are unique in the medical bibliography of Byzantium and were described by the famous physician of the 7th century, Paul of Aegina. The latter describes the techniques of reconstruction of hermaphrodites learned from the now lost work of the great surgeon of the 1st century AD, Leonidas from Alexandria. Paul of Aegina presents, with some ethical reservation the scientific methods of castration used by surgeons only in cases of acts of God or for serious health reasons, where they were obliged to operate. The authors furthermore present the legal position of the state and the church in relation to a phenomenon so widespread in Byzantium as castration.

Byzantium↗

PubMed1995

The phallic castration complex and primary femininity: paired developmental lines toward female gender identity.

I suggest that two developmental lines contribute to the achievement of female gender identity. One is rooted in the phallic castration complex, and the other in primary femininity. Far from being mutually exclusive, the two comprise necessary aspects of every girl's progress toward becoming a woman. To that extent, every woman's analysis will include the analysis of compromise formations that emerge from both. In distinguishing clinical manifestations of each developmental line, I suggest that it may be useful to conceptualize primary femininity and the phallic castration complex as affect-defense configurations which incorporate two fundamentally different ideas about danger. In conflicts of primary femininity, danger is anticipated: anxiety is the signal for compromise formation, since what is actually possessed (the female genital) is valued and is therefore imagined as subject to danger. In the phallic castration complex, danger is imagined already to have occurred. Depressive affect becomes the primary motive for defense, based on a fantasy that what is valued (the male genital) has already been lost. This distinction may facilitate our efforts to specify exactly how recent revisions in theories of female development have explicit implications for practice.

Adult↗