Effect of α2u-globulin on serum concentration of gonadotrophins and testicular activity in oestrogen-treated rats

1983 ◽  
Vol 96 (2) ◽  
pp. 321-327 ◽  
Author(s):  
N. M. Biswas ◽  
P. K. Ghosh ◽  
K. K. Ghosh ◽  
O. W. Neuhaus

Adult male rats were given injections of oestradiol-17β (50 μg/100 g body wt per day) for 7 days. When they were killed 14 days after the last injection, serum levels of gonadotrophins and testosterone and weights of accessory sex organs were less, testicular 17β-hydroxysteroid dehydrogenase 17β-HSD activity was suppressed and spermatogenesis was inhibited. Administration of α2u-globulin (1·5 mg/day) for 14 days to oestrogen-treated rats and for 10 days to control rats resulted in increased concentrations of gonadotrophins and testosterone in the serum. Accessory sex organ weight and spermatogenesis appeared to be normal while 17β-HSD activity increased in oestrogen-treated rats after treatment with α2u-globulin. It was concluded that α2u-globulin has an effect on testicular function in oestrogenized rats by inducing gonadotrophin and testosterone synthesis.

1990 ◽  
Vol 126 (3) ◽  
pp. 431-435 ◽  
Author(s):  
H. Mandal ◽  
P. K. Ghosh ◽  
N. M. Biswas

ABSTRACT Adult male rats were given s.c. injections of melatonin (400 μg/100 g body weight per day) for 14 days. On day 15, the weights of the testis and accessory sex organs were less, testicular 17β-hydroxysteroid dehydrogenase (17β-HSD) activity was inhibited, spermatogenesis was suppressed and serum levels of gonadotrophins, testosterone and α2u-globulin were decreased compared with control animals injected with vehicle. In a third group of rats given the same dose of melatonin for 14 days, administration of dihydrotestosterone (DHT) at a dose of 25 μg/100 g body weight per day on days 8–14 resulted in serum levels of α2u-globulin, FSH, LH and testosterone and testicular 17β-HSD activity similar to those seen in vehicle-injected control animals. Weights of the testes and accessory sex organs and spermatogenesis were normal after administration of DHT in melatonintreated rats. In another group of rats, the depressive effects of melatonin treatment on plasma gonadotrophins were reversed by the administration of α2u-globulin on days 8–14. It was concluded that treatment with DHT prevents the depressive action of melatonin on testicular function by inducing the synthesis of α2u-globulin. Journal of Endocrinology (1990) 126, 431–435


1994 ◽  
Vol 140 (3) ◽  
pp. 343-347 ◽  
Author(s):  
N M Biswas ◽  
P K Ghosh ◽  
R Biswas ◽  
D Ghosh

Abstract Adult male rats were thyroidectomized and killed after 22 days of treatment. Thyroidectomy lowered the weights of testes and accessory sex organs, decreased the activities of testicular Δ5-3β- and 17β-hydroxysteroid dehydrogenases (HSD), and diminished spermatogenesis, serum levels of testosterone and α2u-globulin. Supplementation with thyroxine at a dose of 5 μg/100 g body weight per day for 21 days or supplementation with α2u-globulin at a dose of 1·5 mg/rat per day for 21 days in thyroidectomized animals partially reversed the decrease in HSD activities and serum concentrations of testosterone and α2u-globulin, while spermatogenesis was restored to normal. The weights of testes and accessory sex organs were also reinstated after supplementation with thyroxine or α2u-globulin in thyroidectomized rats in comparison with thyroidectomized animals. It was concluded that α2u-globulin may be an intermediary in the thyroid hormone control of testicular function. Journal of Endocrinology (1994) 140, 343–347


1976 ◽  
Vol 81 (1) ◽  
pp. 198-207 ◽  
Author(s):  
H. L. Verjans ◽  
K. B. Eik-Nes

ABSTRACT Effect of intramuscular administration of ACTH or dexamethasone on blood serum levels of testosterone, LH and FSH was examined in intact and castrated, adult, male rats. Six IU ACTH or 1 mg dexamethasone were given daily for 7 days. Corticotrophin treatment had no influence on circulating testosterone, LH and FSH in intact or castrated male rats. Dexamethasone administration resulted in a slight elevation of serum FSH in intact animals but not in castrates. LH and testosterone remained normal in both intact and castrated animals injected with dexamethasone. Under our conditions of study the secretions from the adrenal gland appear to be insignificant for the regulation of pituitary secretion of gonadotrophins in the male rat.


QJM ◽  
2020 ◽  
Vol 113 (Supplement_1) ◽  
Author(s):  
M M Elshawwa

Abstract Background Obesity is associated with insulin resistance, type2 diabetes, dyslipidemia and cardiovascular diseases. Apelin and chemerin are identified as adipokines and adipose tissue markers. Several adipose-derived peptides are known to influence food intake, including apelin, whose expression is regulated by insulin and chemerin. Oxidative stress thought to be involved in the development of complications associated with obesity. Objective To study the nature of correlation between serum and liver levels of apelin, chemerin and oxidative parameters in obese rats with and without antioxidant. Aiming to clarify the pathophysiology of obesity. Material and Methods Thirty adult male albino rats, divided into three equal groups. Group I (control), group II (obese) and group III (obese and Lepidium sativum (LS) as an antioxidants). At the end of the experiment, blood samples were collected for estimation of the serum levels of chemerin, apelin, fasting glucose, insulin, insulin resistance (IR), lipid profile, reduced glutathione (GSH) and malondialdehyde (MDA). In addition to tissue homogenous extracts of liver were taken for the levels of MDA, CAT, chemerin and apelin. Results After eight weeks, high fat diet group showed a significant increase in serum levels of apelin, chemerin, fasting glucose, insulin, IR, total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C) & MDA and a significant decrease in high-density lipoprotein cholesterol (HDL-C) & GSH. HFD also caused a significant increase in tissue levels of MDA, CAT & chemerin and a significant decrease in apelin, compared to control group. While addition of LS to HFD caused a significant decrease in serum levels of apelin, chemerin, fasting glucose, insulin, IR, TC, TG, LDL-C & MDA and a significant increase in HDL-C & GSH. LS also caused a significant decrease in tissue levels of MDA, chemerin & insignificant decrease in CAT and a significant increase in apelin, compared to HFD group. Conclusion This study showed a significant positive correlation between liver & serum chemerin and between liver and serum MDA. On the other hand, it showed a significant negative correlation between liver and serum apelin and liver CAT and serum GSH


1961 ◽  
Vol 36 (2) ◽  
pp. 299-309 ◽  
Author(s):  
W. Hohlweg ◽  
G. Dörner ◽  
P. Kopp

ABSTRACT In adult male rats subcutaneous injections of 50 μg dienoestrol [3,4-bis (p-hydroxyphenyl)-hexa-2,4-diene] diacetate, given twice weekly, produced an inhibition of spermiogenesis and sexual behaviour resulting in total sterility. By one intratesticular implantation of 3 mg testosterone these alterations could be prevented and even rechanged in spite of continued oestrogen administration. These results prove an important direct influence of testosterone on the generative testicular function.


1977 ◽  
Vol 84 (4) ◽  
pp. 842-849 ◽  
Author(s):  
H. L. Verjans ◽  
K. B. Eik-Nes

ABSTRACT Effects of subcutaneous administration of various doses of different steroids on serum levels of LH and FSH in normal, adult male rats were investigated. Each steroid was injected daily during 7 days in doses of 50, 25, 12.5 or 6.25 μg per 100 g body weight. Ring A 5α-reduced testosterone metabolites exerted high activity in suppressing serum LH and FSH levels. 5α-Androstane-3β,17β-diol had in the doses tested, however, no such effects on serum gonadotrophins. Serum LH concentrations in normal rats appeared more sensitive to steroid treatment than serum FSH concentrations.


1994 ◽  
Vol 266 (4) ◽  
pp. E676-E681
Author(s):  
G. T. Taylor ◽  
J. Scherrer ◽  
J. Weiss ◽  
J. Pitha

Adult male rats (n = 48) were castrated and treated daily for 4 wk with adrenal steroids in the presence or absence of adjuvant testosterone. Dehydroepiandrosterone (DHEA), DHEA sulfate, and androstenedione (2 mg/kg body wt) were administered as cyclodextrin complexes to mimic the pharmacodynamics of the endogenous products. Although they are the substrates for testosterone synthesis in target tissues, supplements of adrenal steroids alone were unable to maintain integrity of sociosexual responses and androgen target tissues after castration. More surprising, groups administered adrenal precursor plus testosterone showed substantial suppression of the typical restoration of reproductive systems in castrates receiving androgen therapy. The adrenal steroids, however, were not functionally identical. Each steroid interacted with testosterone to leave its own distinctive “footprint” on androgen-sensitive systems. The conclusion is that the endogenous adrenal products are not simply passive precursors of testosterone. Adrenal steroids may serve as endocrine regulators of androgen bioavailability and bioactivity.


1991 ◽  
Vol 124 (1) ◽  
pp. 76-82 ◽  
Author(s):  
P. K. Ghosh ◽  
N. M. Biswas ◽  
D. Ghosh

Abstract. The present study was performed on immature male rats aged 35 days. Subcutaneous injections of lithium chloride at a daily dose of 2.0 mg/kg for 15 days resulted in significant inhibition of spermatogenesis at stage VII of the seminiferous epithelial cycle. Spermatogonia A, preleptotene spermatocytes and step 7 spermatids were decreased in number in comparison to controls. Serum levels of FSH, LH, PRL, and testosterone were decreased. Activities of testicular Δ5-3β-hydroxysteroid dehydrogenase and 17β-hydroxysteroid dehydrogenase were suppressed along with a low caudal epididymal sperm count in comparison with controls. When the treatment was prolonged for 20 and 25 days, it showed an additional significant diminution in accessory sex organ weights and number of midpachytene spermatocytes at stage VII in comparison to control animals of corresponding age. It is concluded that lithium has an adverse effect on testicular function in immature rats by reducing serum levels of FSH, LH, PRL, and testosterone. Furthermore, since hormonal changes and altered spermatogenic activities were evident when the serum concentration of lithium was within the therapeutic range, our data may have some potential clinical implications.


1987 ◽  
Vol 113 (1) ◽  
pp. 111-116 ◽  
Author(s):  
R. F. A. Weber ◽  
M. P. Ooms ◽  
J. T. M. Vreeburg

ABSTRACT The effects of hyperprolactinaemia on serum levels of LH were investigated in adult male rats of the R × U strain. Hyperprolactinaemia was induced by three pituitary grafts under the kidney capsule, transplanted on day 0 of each experiment. Special attention was paid to the contribution of prolactin-stimulated testes, adrenals and corticosterone. In experiment 1, hyperprolactinaemia significantly reduced the serum concentrations of LH in intact rats. In spite of a significant increase in the serum levels of corticosterone, serum testosterone was not significantly affected by hyperprolactinaemia. The weights of both the adrenals and accessory sex glands were significantly increased at autopsy. In experiment 2, treatment with 10 mg corticosterone s.c. daily from day 14 to day 28 after pituitary grafting significantly reduced serum levels of both LH and testosterone. The suppression of testosterone in the hyperprolactinaemic corticosterone-treated animals was significantly less than in the corticosterone-treated control animals. The weights of the accessory sex glands were significantly increased in the hyperprolactinaemic animals. In experiment 3, rats were adrenalectomized and half of them were substituted with corticosterone. Serum testosterone levels significantly increased in both hyperprolactinaemic adrenalectomized rats and in adrenalectomized corticosterone-treated animals without any significant effect on serum LH. Again the weights of the accessory sex glands were significantly increased in the hyperprolactinaemic animals. In experiment 4, rats were adrenalectomized, gonadectomized and corticosterone treated on day 0 and then implanted with a 2, 1·5 or 1 cm silicone elastomer capsule containing testosterone. On day 28 after pituitary grafting, LH levels were significantly suppressed in animals with a 2 or 1·5 cm testosterone implant. The weights of the accessory sex glands were not increased in the hyperprolactinaemic animals. These results show that in the male rat the inhibitory effects of hyperprolactinaemia on serum LH levels may be due to (1) increased sensitivity of the hypothalamic-pituitary axis to the negative feedback action of testosterone by prolactin and by the prolactin-stimulated corticosterone secretion and (2) stimulation of testicular testosterone secretion by prolactin, which can also explain the increased weights of the accessory sex glands. Even in the presence of high serum concentrations of corticosterone, stimulation of testicular testosterone secretion by prolactin was observed. J. Endocr. (1987) 113,111–116


1987 ◽  
Vol 114 (1) ◽  
pp. 84-89
Author(s):  
P. Negri-Cesi ◽  
F. Celotti ◽  
R. C. Melcangi ◽  
M. Zanisi ◽  
M. Motta

Abstract. The aim of the present experiments was to analyze whether the inhibitory effect exerted by testosterone on FSH release might be mediated by the intracerebral transformation of the hormone into oestrogenic metabolites. Advantage has been taken of the availability of the potent antioestrogen tamoxifen. Two series of experiments have been performed. In the first one, adult male rats have been castrated and submitted, beginning immediately after surgery, to a 6-day treatment with testosterone propionate (2 mg/rat/day), tamoxifen (50 or 200 μg/rat/day) or testosterone propionate (2 mg/rat/day) plus tamoxifen (either 50 or 200 μg/rat/day). In the second experiment, adult male rats have been castrated and submitted to the same 6-day treatments, beginning 4 weeks following orchidectomy. In both experiments, the animals were killed 24 h after the last injection, and serum levels of FSH and LH have been measured by radioimmunoassays. The results have clearly shown that, in both experiments, the administration of testosterone results in a significant decrease of serum FSH and in a total suppression of LH release. The administration of tamoxifen, in either dose, does not modify the elevated serum FSH and LH levels present in the orchidetomized animals, and does not antagonize the inhibitory effect on FSH and LH secretion exerted by the concomitant treatment with testosterone propionate. It is concluded that testosterone inhibits FSH secretion in orchidectomized rats acting as such, and not following aromatization to oestrogens.


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