Effects of trenbolone acetate on adrenal function and hepatic enzyme activities in female rats

1983 ◽  
Vol 98 (1) ◽  
pp. 121-127 ◽  
Author(s):  
K. M. Thomas ◽  
R. G. Rodway
Keyword(s):  
Plasma Corticosterone ◽  
Tyrosine Aminotransferase ◽  
Adrenal Function ◽  
Female Rats ◽  
Hepatic Enzyme ◽  
Corticosterone Concentration ◽  
Trenbolone Acetate ◽  
Phosphoenol Pyruvate ◽  
Corticosterone Treatment ◽  
And Control

The effects of the anabolic steroid trenbolone acetate (TBA) on adrenal function and hepatic enzyme activity have been studied in growing female rats. Treatment with TBA resulted in a decrease in the peak of plasma corticosterone concentration which occurred during the afternoon. The enzymes tyrosine aminotransferase (TAT) and phosphoenol-pyruvate carboxykinase were measured in the livers of treated and control rats. Activities of both enzymes were maximal at 22.00 h, but that of TAT was reduced in TBA-treated rats. After injection of ACTH, TBA-treated rats showed a smaller increase in plasma corticosterone than did controls. Treatment with TBA did not affect the induction of TAT activity after corticosterone treatment. All TBA-treated rats grew significantly faster than controls and the possible relevance of this reduced adrenal function to the increased growth rate is discussed.

Dissociation of adrenal corticosteroid production from ACTH in water-restricted female rats

1981 ◽  
Vol 241 (1) ◽  
pp. R21-R24 ◽  
Author(s):  
R. G. Doell ◽  
M. F. Dallman ◽  
R. B. Clayton ◽  
G. D. Gray ◽  
S. Levine
Keyword(s):  
Corticosterone Level ◽  
Plasma Corticosterone ◽  
Female Rats ◽  
Adrenocorticotrophic Hormone ◽  
Corticosterone Concentration ◽  
Acth Concentration

These experiments were undertaken to investigate the mechanism whereby a precipitous drop in plasma corticosterone concentration is brought about following drinking in rats on a restricted water schedule. No alteration in adrenocorticotrophic hormone (ACTH) output was found, nor was catabolism of corticosterone sufficient to account for the drop. It is concluded that corticosterone level is controlled under these conditions by a mechanism independent of ACTH concentration.

INTERRELATIONSHIPS OF PITUITARY AND PLASMA CORTICOTROPHIN AND PLASMA CORTICOSTERONE IN ADRENALECTOMIZED AND STRESSED, ADRENALECTOMIZED RATS

1974 ◽  
Vol 63 (1) ◽  
pp. 213-222 ◽  
Author(s):  
JULIA C. BUCKINGHAM ◽  
J. R. HODGES
Keyword(s):  
Plasma Corticosterone ◽  
Prolonged Treatment ◽  
Delayed Effect ◽  
Plasma Acth ◽  
Corticosterone Concentration ◽  
Before And After ◽  
Small Rise ◽  
Acth Concentration ◽  
Corticosterone Treatment ◽  
Adrenalectomized Rats

SUMMARY Changes in pituitary and plasma corticotrophin (ACTH), estimated by redox bioassay, were correlated with changes in plasma corticosterone in adrenalectomized rats, with and without corticosterone treatment, before and after exposure to stress. After adrenalectomy, the plasma ACTH concentration was persistently increased. The pituitary ACTH content declined and then increased markedly. These changes were prevented by physiological doses of corticosteroids. Stress caused only a small rise in the plasma ACTH concentration in intact and sham-operated rats but a marked increase in adrenalectomized animals. This exaggerated response was reduced to normal by physiological doses of corticosterone. Prolonged treatment with higher doses of corticosterone was necessary to abolish completely the adrenocorticotrophic response to stress. However, one injection of the steroid, in a dose sufficient to raise the plasma corticosterone concentration to a similar level, did not impair the stress-induced release of ACTH. The results suggest that the synthesis and the basal release of ACTH are directly controlled by the concentration of corticosteroid in the blood, but the corticosteroids exert only a delayed effect in modulating the stress-induced release of the hormone.

PITUITARY-ADRENAL ACTIVATION IN RATS WITH HEREDITARY HYPOTHALAMIC DIABETES INSIPIDUS

1967 ◽  
Vol 54 (1) ◽  
pp. 155-165 ◽  
Author(s):  
Akira Arimura ◽  
Takashige Saito ◽  
Cyril Y. Bowers ◽  
Andrew V. Schally
Keyword(s):  
Diabetes Insipidus ◽  
Normal Structure ◽  
Plasma Corticosterone ◽  
Posterior Pituitary ◽  
Corticosterone Concentration ◽  
Corticotrophin Releasing Factor ◽  
Significant Difference ◽  
The Difference ◽  
Hereditary Hypothalamic Diabetes Insipidus ◽  
And Control

ABSTRACT Pituitary adrenal activation in rats with hereditary hypothalamic diabetes insipidus (DI) and normal control rats (Brattleboro strain) was studied under various conditions. Plasma corticosterone concentration was essentially the same in resting DI and control rats. No significant difference in plasma corticosterone was observed after giving the animals ether, histamine, vasopressin or acetylcholine. Since DI rats lack vasopressin, these findings provide some evidence that vasopressin is unlikely to be the physiological corticotrophin releasing factor (CRF). Epinephrine induced a smaller increase in plasma corticosterone in DI rats than control animals, but the difference was not statistically significant. However, intraperitoneal injection of 0.9% saline resulted in significantly less elevation of plasma corticosterone in DI rats than normal. This suggests certain differences in responses between normal and DI rats depending upon the intensity or nature of the stress. Hypothalamic CRF in control and DI rats was determined using rats treated with chlorpromazine, morphine and Nembutal®. The CRF of hypothalami of DI rats was about half of that of control animals. In the extracts of posterior pituitary lobes, corticotrophin (ACTH) activity was found in almost the same amount in DI and control rats. The posterior pituitary lobe of DI rats lacked CRF activity when tested in neurohypophysectomized rats. Histological examination of the adrenals of DI rats revealed normal structure, suggesting normal ACTH secretion at rest.

PITUITARY–ADRENAL FUNCTION IN THYROPARATHYROIDECTOMIZED MALE AND FEMALE RATS

1976 ◽  
Vol 71 (1) ◽  
pp. 47-50 ◽  
Author(s):  
J. D. DUNN ◽  
M. E. HESS
Keyword(s):  
Stress Response ◽  
Peak Plasma ◽  
Plasma Corticosterone ◽  
Adrenal Function ◽  
Female Rats ◽  
Adrenocortical Function ◽  
Dark Phase ◽  
Intact Control ◽  
Male And Female ◽  
Male And Female Rats

SUMMARY The influence of thyroid hormones on pituitary–adrenal function was assessed by studying several aspects of adrenocortical function approximately 30 days after thyroparathyroidectomy (TPTx). Both male and female rats showed evidence of rhythmic adrenocortical activity; peak plasma corticosterone levels occurred just before the dark phase of the lighting schedule. Only the amplitude of the rhythm appeared altered by TPTx. Peak plasma corticosterone levels in TPTx male and female animals were less (P < 0·05) than corresponding levels in intact control rats. Both sexes showed significant responses to stress, but the morning stress response in TPTx females was less (P < 0·01) than the stress response in intact controls. Concomitant with the reduced stress response, the adrenocortical response to exogenous ACTH was reduced in TPTx female rats.

PLASMA AND ADRENAL CORTICOSTERONE CONCENTRATION DURING THE DIFFERENT PHASES OF THE SEXUAL CYCLE IN NORMAL FEMALE RATS

1971 ◽  
Vol 68 (1_Supplb) ◽  
pp. S77
Author(s):  
D. Raps ◽  
P. L. Barthe ◽  
G. Meglioli ◽  
P. A. Desaulles
Keyword(s):  
Female Rats ◽  
Sexual Cycle ◽  
Normal Female ◽  
Corticosterone Concentration ◽  
Adrenal Corticosterone

Effects of progesterone induced postmaturity on CBG and pituitary-adrenal activities in the rat foetus

1986 ◽  
Vol 112 (3) ◽  
pp. 396-403 ◽  
Author(s):  
Jean Paul Dupouy ◽  
Alain Chatelain
Keyword(s):  
Binding Capacity ◽  
Sharp Decrease ◽  
Plasma Corticosterone ◽  
Corticosterone Concentration ◽  
Rat Pups ◽  
Body Weights ◽  
Normal Rat ◽  
Severe Jaundice ◽  
High Level ◽  
Subsequent Rise

Abstract. CBG and pituitary-adrenal activities were investigated in intact rat foetuses, in newborns spontaneously delivered by vaginal way and in postmature foetuses from mothers with delayed parturition caused by daily progesterone injection from day 20 of gestation. The postmature foetuses had lower body weights and higher adrenal weights on day 22, 23 and 24 of gestation than newborns of the same conceptional age. The corticosterone binding capacity of the plasma as well as the binding capacity of CBG for corticosterone decreased in intact foetuses for the last 3 days of gestation and stayed very low in pups from day 0 to day 8 postpartum. These parameters decreased more slowly in postmature foetuses; however, the differences between the latter and intact foetuses or newborns were not statistically significant. Similar evolution occurred in intact pregnant and suckling females as well as in females with prolonged gestation. The fall in CBG activity in normal rat pups and the subsequent rise in free steroids could explain a sharp decrease in plasma ACTH levels as well as the drop in adrenal and plasma corticosterone concentration. In foetuses with prolonged gestation, the same phenomenon did not occur. Stress conditions produced by maintaining growing foetuses in utero and the development of severe jaundice maintained high ACTH levels. In contrast, the fall in adrenal and plasma corticosterone concentrations in spite of the high level of circulating ACTH could be mainly due to the progesterone inhibition of the steroidogenic activity of the foetal adrenals.

scholarly journals Effects of a new thyrotropic drug isolated from Potentilla alba on the male reproductive system of rats and offspring development

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Lubov V. Krepkova ◽  
Valentina V. Bortnikova ◽  
Aleksandra N. Babenko ◽  
Praskovya G. Mizina ◽  
Vladimir A. Mkhitarov ◽  
...  
Keyword(s):  
Animal Study ◽  
Male Fertility ◽  
Wistar Rats ◽  
Medical Condition ◽  
Adverse Outcomes ◽  
Female Rats ◽  
Childbearing Age ◽  
Offspring Development ◽  
Male Wistar Rats ◽  
And Control

Abstract Background The dysfunction of the thyroid gland is a common medical condition. Nowadays, patients frequently use medicinal herbs as complementary or alternative options to conventional drug treatments. These patients may benefit from treatment of thyroid dysfunctions with Potentilla alba L. preparations. While it has been reported that Potentilla alba preparations have low toxicity, nothing is known about their ability to affect reproductive functions in patients of childbearing age. Methods Male Wistar rats were orally treated with a thyrotrophic botanical drug, standardized Potentilla alba Dry Extract (PADE), at doses 8 and 40 times higher than the median therapeutic dose recommended for the clinical trials, for 60 consecutive days. Male Wistar rats receiving water (H2O) were used as controls. After completing treatment, half of the PADE-treated and control males were used to determine PADE gonadotoxicity, and the remaining half of PADE-treated and control males were mated with intact females. Two female rats were housed with one male for two estrus cycles. PADE effects on fertility and fetal/offspring development were evaluated. Results Herein, we report that oral treatment of male Wistar rats with PADE before mating with intact females instigated marked effects on male reproductive organs. Treatment significantly decreased the motility of the sperm and increased the number of pathological forms of spermatozoa. Additionally, a dose-dependent effect on Leydig cells was observed. However, these PADE effects did not significantly affect male fertility nor fetal and offspring development when PADE-treated males were mated with intact females. Conclusions PADE treatment of male rates negatively affected sperm and testicular Leydig cell morphology. However, these changes did not affect male fertility and offspring development. It is currently not known whether PADE treatment may affect human male fertility and offspring development. Therefore, these results from an animal study need to be confirmed in humans. Results from this animal study can be used to model the exposure-response relationship and adverse outcomes in humans.

Effects of trenbolone acetate and testosterone on growth and on plasma concentrations of corticosterone and ACTH in rats

1990 ◽  
Vol 126 (3) ◽  
pp. 461-466 ◽  
Author(s):  
M. N. Sillence ◽  
R. G. Rodway
Keyword(s):  
Weight Gain ◽  
Growth Response ◽  
Plasma Concentrations ◽  
Female Rats ◽  
Male Rats ◽  
Adrenal Weight ◽  
Trenbolone Acetate ◽  
Male And Female Rats ◽  
Age Related ◽  
Old Rats

ABSTRACT The effects of trenbolone acetate (TBA) on growth and on plasma concentrations of corticosterone were examined in male and female rats. At 5 weeks of age, rats were injected with TBA (0·8 mg/kg) dissolved in peanut oil, or with oil alone, daily for 10 days. In female rats, TBA caused an increase in weight gain (20–38%), a reduction in adrenal weight (19%) and a reduction in plasma concentrations of corticosterone (55%). In contrast, TBA-treated male rats showed no significant increase in weight gain, no significant change in adrenal weight and no reduction in plasma concentrations of corticosterone. The mechanism by which adrenal activity was suppressed in TBA-treated female rats was examined and the response compared with that to testosterone. Female rats (8 weeks old) were injected daily either with oil vehicle, TBA (0·8 mg/kg) or testosterone propionate (0·8 mg/kg). Testosterone increased weight gain (24%), but the growth response to TBA treatment was significantly greater (97%). A reduction in plasma concentrations of corticosterone (45%) was again observed in response to TBA. However, testosterone increased plasma concentrations of corticosterone (52%) above those of control values. Neither androgen affected plasma concentrations of ACTH. Finally, the effects of TBA were examined in 6-week-old female rats, to characterize further the apparent age-related increase in responsiveness. The growth response of 6-week-old rats (60–74%) was intermediate between that seen in 5- and 8-week-old animals. It is concluded that part of the anabolic activity of TBA may be related to a reduction in circulating concentrations of corticosterone. The effect of TBA on corticosterone concentrations differs from that of the natural androgen, testosterone, and does not appear to be mediated by a reduction in plasma concentrations of ACTH. Journal of Endocrinology (1990) 126, 461–466

Adrenocortical function in aging exercise-trained rats

1977 ◽  
Vol 43 (5) ◽  
pp. 839-843 ◽  
Author(s):  
J. A. Severson ◽  
R. D. Fell ◽  
J. G. Tuig ◽  
D. R. Griffith
Keyword(s):  
Age Groups ◽  
Plasma Corticosterone ◽  
Treadmill Running ◽  
Adrenocortical Function ◽  
Elevated Plasma ◽  
Corticosterone Concentration ◽  
Relationship Of ◽  
The Relationship

Plasma corticosterone concentrations and in vitro adrenal secretion of corticosterone were determined in exercise-trained rats. Rats, 100, 200, and 300 days of age, were trained for a 10-wk period by treadmill running. Following the training program, rats were subjected to an acute bout of swimming. Acute swimming elevated plasma corticosterone concentrations in all age groups. At 170 days of age, the plasma corticosterone concentration following swimming was higher in exercise-trained rats than in controls. The opposite was true of acutely swum rats at 270 and 370 days of age. Acute swimming elevated the in vitro adrenal gland response to adrenocorticotropic hormone stimulation in control rats at all ages and in trained rats at 170 days of age. The in vivo relationship of epinephrine and the pituitary adrenal system is suggested as a mechanism which could have caused this response. The relationship of secretion rates to plasma corticosterone concentrations indicated that extra-adrenal mechanisms, such as decreased turnover, were also responsible for the elevated plasma corticosterone levels observed in response to acute swimming.

scholarly journals Evaluation of optimal conditions for arginase activity in streptozotocin induced diabetic rats

2012 ◽  
Vol 50 (No. 2) ◽  
pp. 69-76 ◽  
Author(s):  
M. Erisir ◽  
E. Ercel ◽  
S. Yilmaz ◽  
S. Ozan
Keyword(s):  
Maximal Activity ◽  
Diabetic Rats ◽  
Arginase Activity ◽  
Female Rats ◽  
Kinetic Properties ◽  
Ph Profile ◽  
Optimum Ph ◽  
Liver And Kidney ◽  
And Control ◽  
Assay Conditions

The assay conditions needed to achieve maximal activity of liver and kidney arginase in diabetic and non-diabetic rats were investigated and compared. The physicochemical and kinetic properties of liver arginase in diabetic and control rats were very similar, those of kidney arginase were significantly different. It was found that preincubation temperature (68&deg;C), preincubation period (20 min), optimum pH (10.1) of liver arginase and K<sub>m</sub> (3.2) for its substrate, L-arginine, did not change in diabetic and non-diabetic rats. As a consequence of diabetes, the optimum Mn<sup>2+</sup> concentration for liver arginase only changed from 1 to 2 mM. Although the preincubation temperature and period for activation of kidney arginase in control rats was unnecessary, they were found to be 56&ordm;C and 12 min in diabetic rats. The pH profile of arginase in kidney of diabetic rats was different from that of control rats. The K<sub>m</sub> value (6.7) of arginase for L-arginine in kidney is unchanged in diabetes whereas a marked decrease in V<sub>max</sub> was found. Optimum Mn<sup>2+</sup> concentration (2 mM) for kidney arginase was unchanged in diabetes. The activity of arginase in liver of diabetic animals was higher 1.5 to 1.7 times than that of controls. Diabetes caused an about 53% decrease of arginase activity in kidney of female rats, 26% in that of males. These findings may suggest an idea that encoded arginases by separate gene loci may be affected differently by the pathological and hormonal status.

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