EFFECTS OF TESTOSTERONE PROPIONATE, 5α-DIHYDROTESTOSTERONE PROPIONATE AND OESTRADIOL BENZOATE ON SERUM LEVELS OF LH AND FSH IN THE CASTRATED ADULT MALE RAT

1974 ◽  
Vol 77 (4) ◽  
pp. 643-654 ◽  
Author(s):  
H. L. Verjans ◽  
K. B. Eik-Nes ◽  
J. H. Aafjes ◽  
F. J. M. Vels ◽  
H. J. van der Molen
Keyword(s):  
Adult Male ◽  
Testosterone Propionate ◽  
Serum Levels ◽  
Seminal Vesicles ◽  
Male Rats ◽  
Male Rat ◽  
Low Doses ◽  
Serum Lh ◽  
Oestradiol Benzoate ◽  
Adult Male Rat

ABSTRACT The influence of treatment with various doses of testosterone propionate, 5α-dihydrotestosterone propionate or oestradiol benzoate on serum levels of LH and FSH (measured by radioimmunoassay) and on weights of ventral prostates and seminal vesicles was investigated in castrated, adult, male rats. For depression of the high, castrate levels of serum gonadotrophins with either of these steroid esters, the inhibition curves were different for LH and for FSH. Serum LH was kept at levels encountered in intact, adult, male rats by lower doses of steroid ester than was serum FSH. Oestradiol benzoate was the most potent suppressor of the serum gonadotrophins among the steroid esters tested, testosterone propionate the least. Treatment with low doses of oestradiol benzoate, however, resulted in serum FSH levels significantly above those of castrates treated with vehicle only. Finally, administration of a synthetic LH-releasing factor to testosterone propionate, 5α-dihydrotestosterone propionate or oestradiol benzoate treated, castrated, adult, male rats resulted in a further release of both LH and FSH. The latter effect was more pronounced in oestradiol benzoate treated castrates than in testosterone propionate or 5α-dihydrotestosterone propionate treated castrates.

TESTOSTERONE AND OESTRADIOL SUPPRESSION OF LH AND FSH IN ADULT MALE RATS: DURATION OF CASTRATION, DURATION OF TREATMENT AND COMBINED TREATMENT

1973 ◽  
Vol 73 (1) ◽  
pp. 11-21 ◽  
Author(s):  
R. S. Swerdloff ◽  
P. C. Walsh
Keyword(s):  
Adult Male ◽  
Testosterone Propionate ◽  
Combined Treatment ◽  
Male Rats ◽  
Low Doses ◽  
Duration Of Treatment ◽  
Serum Lh ◽  
Oestradiol Benzoate ◽  
Hypothalamic Pituitary Axis ◽  
Androgen Effect

ABSTRACT The effects of androgens and oestrogens on serum LH and FSH in castrated rats were evaluated with regard to the modifying influences of duration of castration, duration of treatment and combined oestrogen-androgen effect. Serum LH was not greatly influenced by these variables. In contrast, serum FSH was shown to be more resistant to suppression by both steroids after at least five days of castration, requiring a longer duration of treatment to be suppressed to intact levels. Combined treatment of submaximally suppressive doses of testosterone propionate and oestradiol benzoate resulted in no additive effect on lowering serum FSH. Low doses of both androgens and oestrogens resulted in elevated levels of serum LH and FSH, suggesting that the adult male hypothalamic-pituitary axis may be responsive to positive feedback. In all studies, testosterone preferentially suppressed serum LH as compared to serum FSH. In contrast, oestradiol administration produced parallel inhibition of both LH and FSH. It is emphasized that neither oestrogen nor androgen alone, nor in combination, resulted in preferential inhibition of serum FSH over LH.

EFFECT OF OESTRADIOL BENZOATE ON PITUITARY AND TESTIS FUNCTION IN THE NORMAL ADULT MALE RAT

1974 ◽  
Vol 77 (4) ◽  
pp. 636-642 ◽  
Author(s):  
H. L. Verjans ◽  
F. H. de Jong ◽  
B. A. Cooke ◽  
H. J. van der Molen ◽  
K. B. Eik-Nes
Keyword(s):  
Adult Male ◽  
Subcutaneous Administration ◽  
Serum Levels ◽  
Testicular Tissue ◽  
Male Rats ◽  
Normal Adult ◽  
Ventral Prostate ◽  
Male Rat ◽  
Oestradiol Benzoate ◽  
Adult Male Rat

ABSTRACT The effects of subcutaneous administration of oestradiol benzoate (EB) on the weights of sex organs and on levels of testosterone and gonadotrophins in normal adult male rats have been studied. Doses of EB varied from 0.01 to 100 μg and were administered daily for seven days. Administration of 100 μg EB resulted in suppression of pituitary LH, while serum LH levels were already decreased after treatment with EB ≧ 1 μg. Pituitary and serum FSH levels were suppressed after administration of 100 and 10 μg EB respectively. Testicular tissue and serum levels of testosterone decreased after treatment with amounts of EB ≧ 1 μg. These decreased androgen levels were also reflected in a concomitant decrease in the weights of the ventral prostate and seminal vesicles. A decrease in the weight of the testes was obtained following a dose of EB ≧ 10 μg.

RELATION BETWEEN CIRCULATING LEVELS OF TESTOSTERONE, LH AND FSH IN INTACT AND CASTRATED, ADULT, MALE RATS AFTER TESTOSTERONE ADMINISTRATION

1975 ◽  
Vol 79 (2) ◽  
pp. 380-386 ◽  
Author(s):  
H. L. Verjans ◽  
H. J. van der Molen ◽  
K. B. Eik-Nes
Keyword(s):  
Adult Male ◽  
Serum Testosterone ◽  
Serum Levels ◽  
Male Rats ◽  
Male Rat ◽  
Normal Male ◽  
Serum Lh ◽  
Adult Male Rat ◽  
Normal Rat ◽  
Testosterone Administration

ABSTRACT Serum levels of LH, FSH and testosterone were measured by radioimmunoassay in intact and castrated, adult, male rats after testosterone was administered subcutaneously for seven days in doses ranging from 25 to 200 μg per 100 g body weight per day. Such treatment increased circulating testosterone both in intact and castrated rats, but its effects on serum gonadotrophins were different in these animal groups. All doses of testosterone suppressed serum LH and FSH in the normal rat. In the castrates, treatment with the lowest dose of testosterone resulted in serum LH levels significantly above the high castrate levels, while serum FSH tended to drop. Administration of the highest doses of testosterone did not depress serum LH and FSH in the castrates to those of intact, normal animals, though serum testosterone in these castrates was much higher than in normal, male rats. It is concluded, that the sensitivity of the hypothalamic-pituitary system for daily, subcutaneous testosterone administration during seven days is not the same in the intact and castrated, adult, male rat and that testicular factors different from testosterone may play a role in regulating production and/or secretion of gonadotrophins by the hypophysis in male animals.

The contribution of corticosterone and testosterone to the suppression of serum LH in hyperprolactinaemic adult male rats with pituitary transplants

1987 ◽  
Vol 113 (1) ◽  
pp. 111-116 ◽  
Author(s):  
R. F. A. Weber ◽  
M. P. Ooms ◽  
J. T. M. Vreeburg
Keyword(s):  
Adult Male ◽  
Serum Testosterone ◽  
Serum Levels ◽  
Male Rats ◽  
Male Rat ◽  
Serum Concentrations ◽  
Testosterone Secretion ◽  
Accessory Sex Glands ◽  
Serum Lh ◽  
Stimulation Of

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

HYPOTHALAMIC-PITUITARY-TESTICULAR SYSTEM AND ADRENOCORTICAL FUNCTION

1976 ◽  
Vol 81 (1) ◽  
pp. 198-207 ◽  
Author(s):  
H. L. Verjans ◽  
K. B. Eik-Nes
Keyword(s):  
Adrenal Gland ◽  
Blood Serum ◽  
Adult Male ◽  
Serum Levels ◽  
Male Rats ◽  
Intramuscular Administration ◽  
Adrenocortical Function ◽  
Male Rat ◽  
Pituitary Secretion ◽  
Slight Elevation

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.

EFFECT OF TESTOSTERONE PROPIONATE ON HYPOPHYSIS OF THE NORMAL YOUNG ADULT MALE RAT

Endocrinology ◽  
1942 ◽  
Vol 31 (3) ◽  
pp. 303-308 ◽  
Author(s):  
PHILIP WAINMAN ◽  
J. D. REESE ◽  
A. A. KONEFF
Keyword(s):  
Young Adult ◽  
Adult Male ◽  
Testosterone Propionate ◽  
Male Rat ◽  
Young Adult Male ◽  
Adult Male Rat

GONADOTROPHIN SUPPRESSION BY STEROIDS IN NORMAL, ADULT MALE RATS

1977 ◽  
Vol 84 (4) ◽  
pp. 842-849 ◽  
Author(s):  
H. L. Verjans ◽  
K. B. Eik-Nes
Keyword(s):  
Body Weight ◽  
High Activity ◽  
Adult Male ◽  
Subcutaneous Administration ◽  
Serum Levels ◽  
Steroid Treatment ◽  
Male Rats ◽  
Normal Adult ◽  
Serum Lh ◽  
Testosterone Metabolites

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.

EFFECTS OF ANTI-OESTROGEN TREATMENT OF NEONATAL MALE RATS ON LORDOSIS BEHAVIOUR AND MOUNTING BEHAVIOUR IN THE ADULT

1978 ◽  
Vol 76 (2) ◽  
pp. 241-249 ◽  
Author(s):  
P. SÖDERSTEN
Keyword(s):  
Testosterone Propionate ◽  
Neonatal Rat ◽  
Male Rats ◽  
Glans Penis ◽  
Male Rat ◽  
Plasma Testosterone ◽  
Oestrogen Treatment ◽  
Oestradiol Benzoate ◽  
Sexual Glands ◽  
Lordosis Behaviour

Male rats were treated daily with 100 μg of the anti-oestrogen ethamoxytriphetol (MER-25) or oil during the first 10 days of life and tested for lordosis behaviour and mounting behaviour as intact adults, after castration and after castration and oestradiol benzoate or testosterone propionate treatment. The MER-25-treated rats showed higher levels of lordosis behaviour than oil-treated rats in all four treatment groups. Under each of these endocrine conditions, except after castration alone, the MER-25-treated rats showed a reduced capacity to ejaculate. Treatment of the neonatal rat with MER-25 reduced body weight in adulthood but did not change the weight of the accessory sexual glands, the testes, the number of cornified papillae on the glans penis or plasma testosterone concentrations during development. The response of the accessory sexual glands and cornified papillae on the glans penis to treatment with oestradiol benzoate or testosterone propionate after castration in adulthood was unaffected by treatment with MER-25. It is suggested that formation of oestrogen in the neonatal male rat brain from testosterone in the circulation inhibits the capacity to show lordosis behaviour and facilitates the capacity to ejaculate in response to gonadal hormone treatment in adulthood.

scholarly journals Some effects of dietary dextrose, fructose, liquid glucose and sucrose in the adult male rat

1966 ◽  
Vol 20 (2) ◽  
pp. 339-347 ◽  
Author(s):  
R. J. L. Allen ◽  
J. S. Leahy
Keyword(s):  
Adult Male ◽  
Body Weight Gain ◽  
Plasma Cholesterol ◽  
Liver Fat ◽  
Male Rats ◽  
Male Rat ◽  
Liver Protein ◽  
Cholesterol Levels ◽  
Adult Male Rat ◽  
The Mean

1. For 26 weeks, adult male rats were fed on diets containing about 80 % of carbohydrate, given as dextrose, fructose, liquid glucose, or sucrose; their performance was compared with that of rats receiving a standard laboratory cubed diet (41 B) containing 60 % of carbohydrate, mainly as starch. 2. More of diet 41 B was eaten than of any of the diets containing sugars, but only with dextrose was the mean body-weight gain significantly lower than with diet 41 B. 3. No significant differences in body length or girth were produced by the different diets. 4. Compared with those of rats given diet 41B, plasma cholesterol levels were significantly in- creased by fructose and sucrose and to a lesser extent by dextrose, but not by liquid glucose. 5. Compared with those given diet 41 B, the rats given fructose had heavier hearts, kidneys and livers, those given sucrose had heavier hearts and livers, and those given dextrose had heavier hearts. Those given fructose had the heaviest kidneys and livers, and heavier hearts than those given liquid glucose. The organ weights of those given liquid glucose and those given diet 41 B were not significantly different. 6. Compared with the values on diet 41B, carcass and liver fat were both significantly increased by sucrose and fructose but not by dex- trose or liquid glucose. With fructose, liver fat was almost double that with dextrose or liquid glucose. 7. Dry-matter contents of whole carcass and liver followed substantially the same pattern as did the fat contents. 8. Liver protein content was significantly lower on the 80 % carbohydrate diets. The reductions were greatest with fructose and sucrose.

Tamoxifen does not block the inhibitory effect of testosterone on FSH release in rats

1987 ◽  
Vol 114 (1) ◽  
pp. 84-89
Author(s):  
P. Negri-Cesi ◽  
F. Celotti ◽  
R. C. Melcangi ◽  
M. Zanisi ◽  
M. Motta
Keyword(s):  
Adult Male ◽  
Testosterone Propionate ◽  
Day Treatment ◽  
Elevated Serum ◽  
Serum Levels ◽  
Inhibitory Effect ◽  
Male Rats ◽  
Concomitant Treatment ◽  
Lh Release ◽  
Series Of Experiments

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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