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.

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.

EFFECTS OF ANDROSTENES, 5α-ANDROSTANES, 5β-ANDROSTANES, OESTRENES AND OESTRATRIENES ON SERUM GONADOTROPHIN LEVELS AND VENTRAL PROSTATE WEIGHTS IN GONADECTOMIZED, ADULT MALE RATS

1976 ◽  
Vol 83 (1) ◽  
pp. 201-210 ◽  
Author(s):  
H. L. Verjans ◽  
K. B. Eik-Nes
Keyword(s):  
Adult Male ◽  
Standard Dose ◽  
Subcutaneous Administration ◽  
Serum Levels ◽  
Inhibitory Effect ◽  
Male Rats ◽  
Ventral Prostate ◽  
Male Rat ◽  
Regulatory Processes ◽  
Organ Systems

ABSTRACT The effects of subcutaneous administration of steroids from the androstene, 5α-androstane, 5β-androstane, oestrene and oestratriene series on serum levels of LH and FSH and on ventral prostate weights were investigated in gonadectomized, adult male rats. Each steroid was administered for seven days in a standard dose of 100 μg per 100 g body weight per day. 5α-Androstanes disubstituted with oxygen in the positions 3 (3-keto or 3α-hydroxy) and 17 (17-keto or 17β-hydroxy) were effective in suppressing either one or both serum gonadotrophins. 5β-Androstanes and androstenes exhibited very little inhibitory effect in this respect. Potent suppression of serum gonadotrophins was observed following treatment with oestratrienes, the presence of only a phenolic A-ring in these oestrogens appeared sufficient for such suppression. 3 or 3β and 17 or 17β disubstituted (keto or hydroxyl) androstenes could entirely or partly prevent ventral prostate weight decrease post-gonadectomy. 5α-Androstane-3α,17β-diol, 5α-androstane-3α,11β,17β-triol and 5α-androstan-17β-ol-3-one were most potent, while 5β-androstanes and oestratrienes had no effect on this decrement. Regulatory processes by steroids at the hypothalamic-pituitary and at the ventral prostate level were not parallel. The results indicate, however, that 3 or 3α and 17 disubstituted (keto or hydroxyl) 5α-reduced testosterone metabolites, of which 5α-androstan-17β-ol-3-one might be the principal one, are the main steroids directing androgenic regulation at both organ systems tested in the mature 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.

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.

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.

II. MANIFESTATION OF THE ANTI-ANDROGENIC ACTION OF A STEROID ESTER TSAA-330 (16β-ETHYL-17β-HYDROXY-4-OESTREN-3-ONE CAPROATE) AND ELUCIDATION OF ITS LONG-LASTING MECHANISM USING A SIMPLE STEROID DETERMINATION TECHNIQUE

1979 ◽  
Vol 92 (3_Supplb) ◽  
pp. S24-S35 ◽  
Author(s):  
Michio Masuoka ◽  
Mutsushi Shikata ◽  
Reiko Fuziwara ◽  
Ryo Nakayama
Keyword(s):  
Adult Male ◽  
General Circulation ◽  
Time Course ◽  
Subcutaneous Administration ◽  
Levator Ani ◽  
Suppressive Effect ◽  
Sesame Oil ◽  
Male Rat ◽  
Accessory Sex Organs ◽  
Adult Male Rat

ABSTRACT Using a simple steroid determination technique, in situ steroid absorption from a subcutaneously injected sesame oil solution in rats was pursued following the time-course changes in the steroid concentration. Based on the knowledge thus obtained, the antiandrogenic effect of a steroidal compound, TSAA-330*, could be manifested in the subcutaneous route. (1) Anti-androgenic steroid TSAA-291* and its esters in the subcutaneously injected sesame oil solution were selectively absorbed into the general circulation at different rates according to their chemical nature and structures, while the oil itself remained at the injected site for a considerably long period. At the injected site where subcutaneous doses of steroids molar equivalent to 50 mg of TSAA-291 were administered in 5 ml/rat of sesame oil, TSAA-291 decreased to the level of 10% of the initial concentration on the 4th day. TSAA-328* decreased slowly to the 50% and 20% levels on the 7th and 21st day, respectively. TSAA-335* decreased more slowly to the 50% level on the 14th day. TSAA-330 decreased most slowly only to the 70% level on the 49th day. (2) A single subcutaneous administration of 200 mg of TSAA-330 suppressed the weight increase of the accessory sex organs caused by a single subcutaneous injection of testosterone caproate (10 mg) in the immature orchiectomized rat. The suppressive effect was obvious from 2 weeks after the administration, and seemed to last for more than two weeks. The levator ani weight was not affected by the administration of TSAA-330. (3) Dose-dependent inhibitions of the accessory sex organs were obtained three weeks after a single subcutaneous administration of 50 to 400 mg of TSAA-330 in the adult male rat. (4) Daily oral administrations of 50 mg of TSAA-291 or TSAA-330 to the adult male rat for 8 days resulted in depression of the accessory sex organs to almost the same extent obtained with either agent. One week after the last administration, however, the weight of the accessory sex organs of the TSAA-291-administered animals recovered to almost the comparable level with the control, whereas a significant after-effect of the inhibition was still evident in the TSAA-330-administered animals.

MODIFICATION OF MALE RAT REPRODUCTIVE TRACT DEVELOPMENT BY A SINGLE INJECTION OF TESTOSTERONE PROPIONATE SHORTLY AFTER BIRTH

1965 ◽  
Vol 50 (2) ◽  
pp. 310-316 ◽  
Author(s):  
H. E. Swanson ◽  
J. J. van der Werff ten Bosch
Keyword(s):  
Reproductive Tract ◽  
Testosterone Propionate ◽  
Pubertal Development ◽  
Testicular Tissue ◽  
Male Rats ◽  
Ventral Prostate ◽  
Male Rat ◽  
Androgenic Activity ◽  
Reduced Rate ◽  
And Control

ABSTRACT Administration of 500 μg testosterone propionate (TP) to male rats within a few days of birth was followed by a reduced rate of growth of the testes and, after initial stimulation, of the seminal vesicles and ventral prostate. While the testes and accessory organs remained permanently smaller in TP-treated rats than in controls, their growth rates showed pubertal accelerations which coincided with those in the controls. On the basis of these criteria, as well as the criterion of spermatogenesis, the time of puberty was not altered by early TP-administration. The weights of the accessory organs considered in relation to the weights of the testes were identical in TP-treated and control rats; testis tubule diameters in TP-treated rats were normal for the age. It is concluded that early TP-administration caused a reduction in the volume of testicular tissue, which involved both tubules and Leydig cells. There were no indications that TP had caused any qualitative changes in the testes: the timing and the pattern of pubertal development (spermatogenesis and androgenic activity) appeared to be normal.

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

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.

Influence of pinealectomy on the suppression of gonadotrophin secretion induced by hyperprolactinaemia in the adult male rat

1983 ◽  
Vol 97 (3) ◽  
pp. 401-407 ◽  
Author(s):  
A. S. McNeilly ◽  
D. W. Lincoln
Keyword(s):  
Pineal Gland ◽  
Adult Male ◽  
Male Rats ◽  
Male Rat ◽  
Gonadotrophin Secretion ◽  
Adult Male Rat ◽  
Pituitary Glands ◽  
Hypothalamic Pituitary Axis

To investigate the role of the pineal gland in the long-term suppression of gonadotrophin secretion induced by prolactin, the effects of pinealectomy were studied in adult male rats with hyperprolactinaemia produced by the transplantation of two pituitary glands under the kidney capsule. Pinealectomy had no effect on basal levels of LH, FSH or prolactin. The presence of pituitary transplants induced a significant twofold increase in prolactin levels and a prolonged suppression in both LH and FSH. These changes were not affected by pinealectomy. Castration resulted in a similar rise in plasma levels of LH and FSH in rats with and without pituitary transplants. In control rats this rise in LH and FSH was reduced by testosterone-containing silicone elastomer implants (s.c) of 10 mm in length and delayed by implants of 30 mm. These rises in LH and FSH were significantly delayed (10-mm implant) or abolished (30-mm implant) in rats with pituitary transplants indicating an increase in sensitivity of the hypothalamic-pituitary axis to the negative feedback effects of testosterone in these animals compared to controls. These responses were not affected by pinealectomy. These results suggest that the pineal gland is not involved in the mechanism whereby pituitary grafts, possibly through their secretion of prolactin, cause long-term suppression of gonadotrophin secretion.

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