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Biotransformation of 1-dehydrotestosterone in the equine male castrate: identification of the neutral unconjugated and glucuronic acid conjugated metabolites in horse urine.

The in vivo biotransformation of (1,2(n)-3H)1-dehydrotestosterone was studied in three equine male castrates and a number of neutral metabolites were identified in the urinary unconjugated and glucuronic acid conjugate fractions by gas chromatography/mass spectrometry. The metabolites were extracted from aliquots of the 0-24 h urine samples by Amberlite XAD-2 and separated into combined unconjugated plus glucuronic acid conjugated and sulphoconjugated fractions by Sephadex LH-20 column chromatography. After enzymatic hydrolysis of the glucuronides, the crude neutral unconjugated steroids plus the aglycones were partially purified by Kieselgel H chromatography and identified as their methyloxime trimethylsilyl derivatives. In the unconjugated fraction, the major metabolites were isomers of androsta-1,4-diene-6,16,17-triol-3-one. In the aglycone fraction a small amount of the parent steroid was present but the major metabolite was the 17 alpha isomer androsta-1,4-dien-17 alpha-ol-3-one. Other metabolites containing the 1,4-dien-3-one group were isomers of androsta-1,4-diene-16,17-diol-3-one and androsta-1,4-diene-6,16-diol-3-one. Reduction of the 4-ene functionality leading to the formation of 5-androst-1-en-16-ol-3,17-dione, 5-androst-1-ene-16,17-diol-3-one and of the 1-ene functionality leading to the formation of testosterone and its further reduction leading to the formation of C19O2 and C19O3 androstane metabolites was observed. Some interesting features on the electron impact fragmentations of the methyloxime trimethylsilyl derivatives of steroids containing a 1,4-dien-3-one group were also observed.

Animals↗

Prostaglandin dehydrogenase activity of rat and rabbit testicular tissues and accessory glands before and after castration.

Rat reproductive tissues contained both 15-hydroxy-prostaglandin dehydrogenase (PGDH) and delta 13-reductase activities, while rabbit tissues exhibited only PGDH activity. In the rat, delta 13-reductase activity was absent in those tissues that had a high specific activity of PGDH and was present in those tissues with a low specific activity. Total specific activity of PGDH was greatest in the testicular capsule, whereas total activity was greatest in the testicular parenchyma of both species. Total PGDH activity was highest in rat seminal vesicles, where it was second only to the testicular parenchyma. Castration significantly increased PGDH activity of the epididymis, prostate, and seminal vesicles of rats, while delta 13-reductase activity disappeared from those tissues. The specific activity of PGDH was greater in the rat than in the rabbit, except for the testicular parenchyma of the rabbit. The greater PGDH activity in rat testicular capsules, compared to those of the rabbit, correlated well with diminished contractility of the rat capsule. PGDH activity of the interstitial cells correlated well with the role of prostaglandins in androgen synthesis.

15-Oxoprostaglandin 13-Reductase↗

Fluid inhibition as a factor in estrogen-induced increase of prostatic weight in castrated rats.

The mechanism by which estrogens inhibit castration atrophy has been investigated morphologically and biochemically utilizing ventral prostate from Copenhagen rats. The suppression of weight loss and gross edematous appearance of the prostate associated with the in vivo effect of 17 beta-estradiol (E2) could not be accounted for by DNA and protein synthesis. Increase in the fluid content in the tissues was confirmed by demonstration of significant increase in the ratio of wet/dry tissue weights. Light microscopy demonstrated that the main effects were on the stroma, characterized by large interglandular areas almost totally devoid of collagen resulting in an edematous appearance. Electron microscope studies showed an abundance of fluid localized adjacent to the capillary endothelium and some red blood cells indicating disturbances in capillary permeability. The combination of a prolactin secretion inhibiting agent with E2 alone, indicating an involvement of prolactin the estrogen effect. Differences in blood prolactin concentration between the strains of rats may influence the sensitivity of the prostate to estrogens.

Animals↗

Transabdominal ultrasonography in the evaluation of patients with advanced prostatic carcinoma: effects of castration and of chronic administration of a gonadotropin releasing hormone agonistic analogue.

Twenty-two patients with advanced prostatic carcinoma were subjected either to orchiectomy (group I, n = 5) or to chronic administration of a gonadotropin releasing hormone agonistic analogue D, Ser (TBU)6, des Gly-NH2(10) LHRH nonapeptide (HOE 766) (group 2, n = 17). Plasma testosterone was similar in both groups prior to treatment (group 1: 636 +/- 129.29, group 2: 580.85 +/- 37.57; X +/- SE). The levels attained in group I were significantly lower (P less than .05) than those of group 2 through eight weeks of follow-up but were similar by the third month. Prostatic size (cm2) as estimated by transabdominal ultrasonography did not differ between the two groups prior to treatment (group 1: 23.6 +/- 3.35, group 2: 21.4 +/- 1.97; X +/- SE). Both therapies resulted in a decrease of prostatic size that was significantly more pronounced (P less than .05) in group I compared with group 2 by the first and third month; by the six month, there was no statistical difference in the prostatic size attained with either therapeutic modality. Persistent suppression of prostatic size was documented in all patients of group 2 chronically (up to 24 months) treated with HOE 766 even when there was evidence of uninhibited or progressive bony metastases. The above data 1) indicate the efficacy of the HOE 766 in inducing medical castration and prostatic shrinkage in advanced carcinoma of the prostate, 2) document the usefulness of transabdominal ultrasound in the follow-up of such patients, and 3) suggest a relationship between the rapidity of tumor shrinkage and Leydig cell suppression.

Buserelin↗

The effects of estradiol-17 beta on the ultrastructure and subcellular distribution of zinc in the prostatic epithelium of castrated rats.

Male Sprague-Dawley rats, previously castrated for a 7-day period, were maintained on either a low or high dose of estradiol-17 beta for 3 days. Some areas of the prostatic epithelium in the lateral lobe exhibited the ultrastructural characteristics of the untreated, intact animals in response to the small dose of estrogen. The ventral lobe by comparison was not similarly affected. This stimulation in the lateral prostate was not reflected by comparable changes in the subcellular distribution of zinc.

Animals↗

Synergic inhibitory effects of the aromatase inhibitor 1-methyl-androsta-1, 4-diene-3, 17-dione and the antiandrogen cyproterone acetate on androstenedione-induced hyperplastic effects in the prostates of castrated dogs.

We examined whether the induction of estrogen-related hyperplastic changes in the prostate (ie, activation and stimulation of the stroma, especially of the smooth muscle) of castrated beagle dogs was reproducible. The effectiveness of the aromatase inhibitor 1-methyl-androsta-1, 4-diene-3, 17-dione (1-Methyl-ADD) in antagonizing such estrogen-related alterations was investigated in comparison with a combined treatment of 1-Methyl-ADD and the antiandrogen CPA. These studies have demonstrated the suitability of the androstenedione model for testing the efficacy of aromatase inhibitors. In addition, it has been demonstrated that an aromatase inhibitor in combination with an antiandrogen can synergically inhibit the glandular and stromal components of the prostate.

Androstenedione↗

Estrogen-mediated exocytosis in the glandular epithelium of prostates in castrated and hypophysectomized dogs.

Glandular cells in the prostate of the intact, adult dog contain numerous, large secretory granules that are released by exocytosis. Following hypophysectomy or castration, the glandular epithelium atrophies and the secretory granules degenerate and eventually disappear. Pharmacologic doses of estradiol-17 beta 17-cyclopentylpropionate cause the regressed glandular cells to synthesize a new population of smaller granules that are also released by exocytosis, even though estrogen is known to inhibit fluid secretion by the canine prostate. Thus, the mechanisms involved in prostatic synthesis and exocytosis of secretory granules are independent of those regulating fluid secretion and are operative in the absence of androgen or pituitary hormones.

Animals↗

Subcellular localization of gonadotropic hormones in pituitary cells of the castrated pig with the use of pre- and post-embedding immunocytochemical methods.

Pre- and post-embedding immunocytochemical methods based on the use of specific antibodies against beta-subunits of porcine LH and FSH were applied to determine the changes occurring in the anterior pituitary of the pig after gonadectomy. The results showed that (1) the total number of immunoreactive gonadotropes increased from 21-25% in control animals to 24-37% in castrated animals; (2) all gonadotropes contained both LH and FSH; (3) several types of immunoreactive LH/FSH cells were revealed; and (4) the two immunocytochemical methods used with dispersed cells localized the hormones in the same subcellular sites. However, the staining intensity in the different locations varied depending on the method applied. With the post-embedding method, a dense reaction product was found in the secretory granules but the cisternae of RER and the Golgi saccules were always slightly reactive. After the pre-embedding method, the staining intensity in the RER-cisternae and in the Golgi saccules was greatly increased. Thus, the two methodological approaches used in this study have permitted to visualize immunocytochemically the gonadotropic hormones not only at the sites of their storage but also along the intracellular pathway of the secretory material, i.e., at the site of its synthesis and during its passage via the Golgi zone.

Animals↗

In vivo estrogen uptake by individual cell types of the rat anterior pituitary after short-term castration-adrenalectomy.

In vivo estrogen uptake was measured in five anterior pituitary cell types of the rat by a quantitative autoradiographic-immunocytochemical technique. In male and female rats that had been castrated and adrenalectomized for one day all five cell types showed nuclear concentration of label one hour after injection of 3H-estradiol. The order of labeling intensity was lactotropes > somatotropes > gonadotropes > corticotropes > thyrotropes. No significant overall sex difference in estrogen uptake was apparent although male pituitaries tended to take up slightly more. Physiological correlates to these data are discussed.

Adrenal Glands↗

Pituitary folliculo-stellate cells immunostained with S-100 protein antiserum in postnatal, castrated and thyroidectomized rats.

Pituitary folliculo-stellate cells and associated cells were studied immunohistochemically throughout the life of male and female rats. The marginal layer cells of the pars distalis and intermedia as well as the folliculo-stellate cells were immunostained with anti-S 100 protein serum. The immunostained folliculo-stellate cells in one section were identified as themselves by their ultrastructural properties on the adjacent section. Corticotrophs, thyrotrophs and prolactin cells, characterized by the stellate shape, were not immunostained with anti-S 100 protein serum. Reactivity for S-100 protein appeared on postnatal Day 6 in the marginal layer cells of the pars intermedia, and appeared on Day 10 in those cells of the pars distalis. No immunostained folliculo-stellate cells appeared before Day 6, but a few of them appeared on Day 10. Thereafter they increased in number, having more intense immunostaining with advancing age. In castrated rats, the immunostained folliculo-stellate cells appeared quite numerously, with branched cytoplasmic processes surrounding the gonadotrophs. In the thyroidectomized rats, however, folliculo-stellate cells lacked ramified cytoplasmic processes, and their topographic affinity for thyrotrophs was negligible.

Age Factors↗

The uptake of radioiodinated 5 alpha-dihydrotestosterone by the prostate of intact and castrated rats.

Radioiodinated steroid 2 alpha-125I-dihydrotestosterone was prepared by direct labeling procedure and subsequently utilized in the distribution studies on Albino Wistar male rats. Maximum radioactivity in the prostate was found 3 h after the administration of the radiolabeled steroid to 24-h castrated animals (1.29%/g wet weight) and to intact rats (0.57%). The pretreatment of animals with dihydrotestosterone yielded lower uptake by the prostate (0.29%-0.30%), epididymis, and testis while it did not influence the distribution in other androgen-insensitive tissues. The carbon-iodine bond was proved to be intact in the radiopharmacon examined and in its metabolites when retained by the rat prostate. The reported results are in line with our previous investigations on in vitro binding of radioiodinated dihydrotestosterone to androgen receptors but indicate also little utility of the same label for the visualization of the prostate gland.

Animals↗

A morphological study of the prostatic lobes and the seminal vesicles of castrated rats injected with oestradiol and/or insulin.

The growth of the ventral and dorsolateral prostate, the coagulating glands and the seminal vesicles was studied morphologically in castrated rats following 21 daily injections of oestradiol benzoate or protamine zinc insulin alone or in combination. Oestradiol benzoate was given in daily doses of 0.010 mg, protamine zinc insulin in daily doses of 10 IU. In the ventral and dorsolateral prostate oestradiol had an androgen-like action inducing epithelial growth and secretory activity in the epithelium. In the seminal vesicles and coagulating glands oestradiol induced an increased fibromuscular growth. Protamine zinc insulin induced growth and secretory activity in the dorsolateral prostate, while no such effect was observed in the other accessory reproductive glands. Protamine zinc insulin accentuated the androgen-like action of oestradiol benzoate on the epithelium of the dorsolateral prostate but did not influence on the increased fibromuscular growth seen after oestradiol in the coagulating glands and the seminal vesicles.

Animals↗

Effect of prepuberal castration on porcine bulbospongiosus muscle.

The histochemical profile and ultrastructural properties of the bulbospongiosus muscle (BSM) fibers from 5-6 month old boars and barrows (castrated at 7 days of age), and intact week old piglets were compared. Based on myosin ATPase, preincubated at pH 4.2, BSM of boars contained predominately intermediately staining fibers, whereas BSM of barrows and piglets had a mixture of staining intensities. Fibers from boar BSM stained intensely for SDH, with subsarcolemmal and diffuse location of reaction product. Staining intensity for SDH was variable in BSM from barrows and piglets, with diffuse location of reaction product. The BSM of boars and barrows contained predominately dark fibers when stained for glycogen and phosphorylase, and the fibers were low in stored lipids. While the fibers were smaller in barrow as compared to boar BSM, ultrastructural differences between boar and barrow BSM were not detectable.

Age Factors↗

The effect of testosterone administration on lead induced zincprotoporphyrin in blood concentration in castrated male rabbits.

The influence of testosterone propionate on the concentration of zincprotoporphyrin in blood (ZPP) of castrated lead treated rabbits was investigated. The experimental design allowed comparison of the relative ZPP increase (RZI) in testosterone treated and non testosterone treated rabbits. Testosterone was administered by subcutaneous injection of 3 mg/kg body weight/day for 7 consecutive days directly prior to the lead exposure, which was performed by subcutaneous injection of 0.50 mg lead acetate/kg body weight, three times a week for 7 weeks. No effect was found on the hemoglobin concentration (Hb) and hematocrit (Ht) and on the increase of body weight during the experiment. But the increase of RZI in the non testosterone treated rabbits was significantly steeper and earlier than in the testosterone treated group. The possible consequences of the findings had been further commented on.

Animals↗

Immune response to the H-X antigen on P815-X2. I. Recombinant inbred strain analysis and lack of effect of castration.

In a preceding report, the detection of an H-2-linked immune response to the H-Xd antigen on the P815-X2 mastocytoma was demonstrated by the significantly increased survival of (C57BL/6 X DBA/2)F1 (B6D2F1) male hybrids (H-Xb) compared with female siblings (H-Xb/H-Xd) after injection with the histocompatible tumor (H-Xd). This interpretation was supported by the absence of this sex effect in reciprocal D2B6F1 hybrids (H-Xd and H-Xd/H-Xb). Additional findings presented in this paper support the conclusion that this sex effect is due to a true immunological response to H-Xd: (a) Reciprocal (DBA/2 X C57BL/6 H-2 mutant)F1 hybrids, as well as D2B6F1, failed to exhibit the sex effect: (b) the demonstration of the sex effect in (BALB/c X DBA/2)F1 and (BALB/c-H-2dm2 X DBA/2)F1 hybrids and in (C57BL/10 X DBA/2)F1 hybrids was consistent with the known H-X incompatibilities between the strains BALB/c and DBA/2 and C57BL/10 and DBA/2, respectively, previously demonstrated by skin grafting; and (c) the sex effect was not abrogated by castration of male B6D2F1 hybrids. Variability in the presence or absence of the sex effect was observed in various [recombinant inbred (RI) X DBA/2]F1 hybrids and may be attributed to the influence of a regulatory non-H-2 gene which is closely linked to the gene coding for mouse kidney-androgen-regulated protein (KAP) but androgen-independent, or to variability in inheritance of the H-Xb allele among the RI lines. It is proposed that the P815-X2 model may be utilized to type RI lines derived from a cross between C57BL/6 and DBA/2 for their H-X genotypes.

Animals↗

Norepinephrine turnover in pineal gland and superior cervical ganglia. Changes after gonadotrophin administration to castrated rats.

The effects of FSH and LH on norepinephrine (NE) turnover in pineal gland and superior cervical ganglia of castrated female rats were examined by measuring the decline of [3H]NE concentration in the organ 30--120 min after a single i.v. injection of the labeled amine. Both FSH and LH treatment significantly decreased [3H]NE turnover in the pineal gland whereas only FSH accelerated it in the ganglia. As compared to controls, the initial uptake of [3H]NE was lower in the pineal gland of FSH- and LH-treated animals, and higher in the superior cervical ganglia of rats injected with FSH. Neither FSH nor LH modified [3H]NE turnover in heart or adrenal gland, nor changed their endogenous catecholamine content. Pineal monoamine oxidase (MAO) activity type B (assaying by using beta-phenylethylamine as substrate) was decreased by FSH or LH injection. Only FSH modified MAO activity in the ganglia by increasing significantly type A enzyme (assaying by using serotonin as substrate). These results suggest that FSH and LH affect significantly NE metabolism in pineal gland and superior cervical ganglia of spayed rats.

Adrenal Glands↗

Histochemistry of the lumenal cell surfaces of the mucosa of the oviducts and the uterus of the rat. Changes in prepuberty, estrous cycle, castration, hormone replacement and pseudopregnancy.

The lumenal surface coat of the rat oviducts and uterine horns have been histochemically characterized at prepuberty, estrous cycle, castration, hormone replacement and pseudopregnancy. Under the EM, the coat was made up of filamentous and globular structures. Histochemical variations suggested that coat components are under endocrine control.

Animals↗