ACTION OF GYNECOGENIC AND ANDROGENIC HORMONES ON THE GONADS AND PITUITARY GLAND OF MATURE MALE RATS

Endocrinology ◽  
1942 ◽  
Vol 31 (6) ◽  
pp. 644-652 ◽  
Author(s):  
CHARLES A. JOËL
Keyword(s):  
Pituitary Gland ◽  
Mature Male ◽  
Male Rats

THE EFFECTS OF TESTOSTERONE AND ITS 5α-REDUCED METABOLITES ON PITUITARY RESPONSIVENESS TO GONADOTROPHIN-RELEASING HORMONE (Gn-RH)

1977 ◽  
Vol 86 (4) ◽  
pp. 728-732 ◽  
Author(s):  
Y. Epstein ◽  
B. Lunenfeld ◽  
Z. Kraiem
Keyword(s):  
Pituitary Gland ◽  
Mature Male ◽  
Male Rats ◽  
Releasing Hormone ◽  
Gonadotrophin Releasing Hormone ◽  
Low Levels ◽  
High Doses ◽  
Dose Dependent ◽  
Stimulation Of

ABSTRACT The aim of this study was to investigate effects of androgens on gonadotrophin release in response to gonadotrophin-releasing hormone (Gn-RH) stimulation in vitro. Hemipituitaries of mature male rats were pre-incubated for 90 min with T, DHT, 3α- or 3β-diol (4 ng or 4 μg/ml medium), and the incubation continued for 240 min after adding Gn-RH (1 ng/ml medium). Gn-RH caused a 4-5-fold rise in the secretion of LH and a 2-fold rise in FSH secretion. The effect of the androgens was dose-dependent. At low levels, T and DHT exerted no effect on Gn-RH-stimulated gonadotrophin release, whereas the two androstanediols (3α- and 3β-diol) augmented the Gn-RH stimulation of both gonadotrophins, though preferentially LH. With high doses of androgens, the results obtained showed: a) no effect of T; b) DHT suppression of the Gn-RH-stimulated FSH release; c) suppression of Gn-RH stimulation by 3α- and 3β-diol regarding both LH and FSH. It is concluded that T exerts through its reduced metabolites a feedback effect on the pituitary gland responsiveness to Gn-RH stimulation.

scholarly journals SUBTOXIC EFFECTS OF SODIUM FLUORIDE ON THE ULTRASTRUCTURE OF PITUITARY GLAND IN RATS

2020 ◽  
Vol 20 (4) ◽  
pp. 133-135
Author(s):  
I.L. Kolisnyk
Keyword(s):  
Electron Microscopy ◽  
Pituitary Gland ◽  
Sodium Fluoride ◽  
Redox Reactions ◽  
Mature Male ◽  
Male Rats ◽  
Partial Reduction ◽  
White Rats ◽  
Subcellular Level ◽  
Fluoride Intoxication

The study aimed at investigating the morphofunctional state of the pituitary gland in white rats under the subtoxic exposure to sodium fluoride. Mature male rats (N = 17), weighing 130-150 g, were intragastrically administered with aqueous solutions of sodium fluoride in a dose of 1/10 LD50 ranged from 20 mg / kg of body weight. The duration of the subacute experiment was 60 days. To assess the morphological rearrangement at the subcellular level of organization of the pituitary gland, electron microscopy was performed. The microscopic study revealed changes in the submicroscopic architecture resulted from dystrophic processes caused by the subtoxic exposure to sodium fluoride. Prolonged sodium fluoride intoxication led to a number of changes in the ultrastructure of the pituitary gland, manifested by the development of intracellular oedema, swelling of mitochondria, changes in the density of their matrix, partial reduction and loss of cristae, vacuolization and expansion of the cisterns of the granular endoplasmic reticulum, an increase in the number of primary lysosomes, in the redistribution of chromatin nucleus and a decrease in the number of ribosomes and glycogen granules. Hemocapillaries showed oedema of endothelial cells, uneven thickening of the basement membrane, vasodilatation with the development of stasis and sludge of erythrocytes. As in the vessels of the hypothalamus, the presence of fibrin and a significant number of platelets has been found. These changes indicate a disruption of bioenergetics associated with the mitochondrial apparatus and the development of hypoxic processes, which lead to a decrease in the activity of redox reactions occurring at the level of intracellular membranes and organelles.

scholarly journals Morphofunctional State of the Mature Rats Pituitary Gland under Readaptation Conditions to the Long Influence of Heavy Metal Salts Complex and Correction with L-Tocopherol

2021 ◽  
Vol 6 (6) ◽  
pp. 245-252
Author(s):  
N. B. Hryntsova ◽  
◽  
A. M. Romanyuk ◽  
O. O. Tymakova ◽  
D. R. Khrin
Keyword(s):  
Heavy Metal ◽  
Pituitary Gland ◽  
Mature Male ◽  
Metal Salts ◽  
Male Rats ◽  
Structural Components ◽  
Adaptive Processes ◽  
Heavy Metal Salts ◽  
Sexually Mature ◽  
Experimental Group

The purpose of the study was to study the morphofunctional rearrangements of the structural components of the adenohypophysis of sexually mature male rats under the condition of a 30-day period of readaptation to the long-term influence of salts of heavy metals (zinc, copper, iron, manganese, lead and chromium) and taking a corrector drug. Materials and methods. The experiment was carried out on 24 white sexually mature male rats, which were divided into 1 control and 1 experimental group. The experimental group consisted of rats that consumed ordinary drinking water for 30 days after 90 days of receiving water saturated with a combination of heavy metal salts: zinc (ZnSO4 7H2O) – 5 mg / l, copper (CuSO4 5H2O) mg / l, iron (FeSO4) – 10 mg / l, manganese (MnSO4 5H2O) – 0.1 mg / l, lead (Pb (NO3) 2) – 0.1 mg / l and chromium (K2Cr2O7) – 0.1 mg / l and L-tocopherol corrector. Results and discussion. With a 30-day period of readaptation to the action of a complex of salts of heavy metals, combined with the intake of a corrector drug L-tocopherol, morphological rearrangements of a nonspecific polymorphic nature developed in the structural components of the pituitary gland: compensatory hypertrophy and increased vascularization of the pituitary gland were observed, the state of rheological properties of the blood improved, the number of chromophiles increased and the number of chromophobes decreased, the processes of cyst formation disappeared, the stress from the adaptive processes in the glandulocytes of the adenohypophysis decreased, namely their secretory activity, the expression of Hsp90α receptors in the cytoplasm of adenocytes significantly increased. Negative rearrangements include an increased value of the fibrous component of the connective tissue of the intertrabecular spaces, increased collagenization of the wall of veins and capillaries, preservation of stromal edema, plethora of hemocapillaries, the presence of a small number of adenocytes with signs of vacuolization of the cytoplasm, balloon dystrophy. Conclusion. A comprehensive study of the structural components of the adenohypophysis of the test animals under the condition of a 30-day period of readaptation to long periods of consumption of heavy metal salts and correction with L-tocopherol certainly indicate a number of adaptive and regenerative morphofunctional changes aimed at reducing the stress of adaptive processes on the part of the adenohypophysis in response to cancel the action of the stress factor

Prolactin release, oestrogens and proliferation of prolactin-secreting cells in the anterior pituitary gland of adult male rats

1986 ◽  
Vol 108 (3) ◽  
pp. 399-403 ◽  
Author(s):  
R. L. Pérez ◽  
G. A. Machiavelli ◽  
M. I. Romano ◽  
J. A. Burdman
Keyword(s):  
Cell Proliferation ◽  
Pituitary Gland ◽  
Adult Male ◽  
Anterior Pituitary ◽  
Pituitary Hormones ◽  
Anterior Pituitary Gland ◽  
Male Rats ◽  
Serum Prolactin ◽  
Prolactin Release ◽  
Experimental Conditions

ABSTRACT Relationships among the release of prolactin, the effect of oestrogens and the proliferation of prolactin-secreting cells were studied under several experimental conditions. Administration of sulpiride or oestradiol released prolactin and stimulated cell proliferation in the anterior pituitary gland of adult male rats. Clomiphene completely abolished the rise in cell proliferation, but did not interfere with the sulpiride-induced release of prolactin. Treatment with oestradiol plus sulpiride significantly increased serum prolactin concentrations and the mitotic index compared with the sum of the stimulation produced by both drugs separately. Bromocriptine abolished the stimulatory effect of oestradiol on the serum prolactin concentration and on cell proliferation. In oestradiol- and/or sulpiride-treated rats, 80% of the cells in mitoses were lactotrophs. The remaining 20% did not stain with antisera against any of the pituitary hormones. The number of prolactin-secreting cells in the anterior pituitary gland significantly increased after the administration of oestradiol or sulpiride. The results demonstrate that treatment with sulpiride and/or oestradiol increases the proliferation and the number of lactotrophs in the anterior pituitary gland of the rat. J. Endocr. (1986) 108, 399–403

scholarly journals Upregulation of Kiss-1 and Gpr54 Genes Expression in Pituitary of Male Rats Following the Central Administration of Neuropeptide Y

2019 ◽  
Vol 4 (4) ◽  
pp. 137-142
Author(s):  
Vahid Azizi ◽  
Shahrbanoo Oryan ◽  
Homayuon Khazali ◽  
Abdolkarim Hosseini
Keyword(s):  
Gene Expression ◽  
Pituitary Gland ◽  
Neuropeptide Y ◽  
Wistar Rats ◽  
Third Ventricle ◽  
Male Rats ◽  
Control Group ◽  
Central Administration ◽  
Reproductive Axis ◽  
Male Wistar Rats

Introduction: The neuropeptide Y (NPY) in the neural circuits of the hypothalamus has a stimulating effect on reproductive activities in mammals. Kisspeptin (KiSS1) is a quintessential neurotransmitter in the reproductive axis which directly stimulates gonadotropin-releasing hormone neurons in the hypothalamus. The distribution of KiSS1 expressing cells in the pituitary was described previously. Despite earlier reports showing the KiSS1 receptor, G-protein coupled receptor 54 (GPR54) expression in the pituitary, the potential physiological roles of kisspeptin at this gland have remained obscure. Accordingly, this study investigated the role of NPY on the relative expression of Kiss1 and Gpr54 genes in the pituitary gland in male Wistar rats. Methods: In general, 20 male Wistar rats weighing 200-250 g in 4 groups (5 in each group) received saline, NPY (2.3 nM), BIBP3226 (NPY receptor antagonist, 7.8 nM), and NPY+ BIBP3226. Then, they received the simultaneous injection of these molecules through the third ventricle of the brain. Finally, the relative mean expressions of Kiss1 and Gpr54 genes in the anterior pituitary were quantitatively analyzed by the real-time polymerase chain reaction. Results: The central injection of NPY increased the relative mean expressions of Kiss1 and Gpr54 genes in the pituitary gland compared to the control group although the injection of BIBP3226 eradicated these effects. However, the gene expression of Gpr54 in the rats receiving NPY coupled with BIBP3226 in hypophysis in comparison to the group receiving only NPY demonstrated a significant reduction (P<0.05). Conclusion: Overall, the central injection of NPY stimulated the gene expression of Kiss1 and Gpr54 in the pituitary gland.

scholarly journals Immunohistochemical localization of melatonin in the rat Harderian gland.

1976 ◽  
Vol 24 (11) ◽  
pp. 1173-1177 ◽  
Author(s):  
G A Bubenik ◽  
G M Brown ◽  
L J Grota
Keyword(s):  
Acinar Cells ◽  
Harderian Gland ◽  
Immunohistochemical Localization ◽  
Mature Male ◽  
Male Rats ◽  
Secretory Cells ◽  
Yellow Fluorescence ◽  
Double Antibody

Using fluorescence and double antibody techniques, melatonin was localized immunohistologically in the secretory cells of the Harderian gland of mature male rats. The presence and quantity of melatonin in the acinar cells seem to correlate with the amount of porphyrins inside the lumen. The specificity was proven by disappearance of yellow fluorescence after saturation of antibody with melatonin or after use of nonspecific antibody only.

Influence of in utero di-n-hexyl phthalate and di-cyclohexyl phthalate exposure on the endocrine glands and T3, T4, and TSH hormone levels of male and female rats: Postnatal outcomes

2020 ◽  
Vol 36 (6) ◽  
pp. 399-416
Author(s):  
Nurhayat Barlas ◽  
Emre Göktekin ◽  
Gözde Karabulut
Keyword(s):  
Pituitary Gland ◽  
Dose Group ◽  
Female Rats ◽  
Male Rats ◽  
High Dose ◽  
Hormone Levels ◽  
Male And Female Rats ◽  
Endocrine Organs ◽  
Body Weights ◽  
Juvenile Stages

The present study was designed to evaluate the effects of di- n-hexyl phthalate (DHP) and di-cyclohexyl phthalate (DCHP) on endocrine organs in rats. Oil control, 20-, 100-, and 500 mg/kg dose groups were selected and administered to pregnant rats on gestational days 6–19 by oral gavage. The neonatal stages of rats continued until postnatal day 20 and the- juvenile stages of rats continued until postnatal day of 32. The rats were allowed to mature until the neonatal and juvenile stages and there after, they were divided into four groups corresponding to the treatment levels. Body and organ weights were recorded, serum was collected, and thyroid, pancreas, pituitary gland, and adrenal gland were removed. There was a decrease in body weights in the 20- and 500mg/kg DHP and in the 20-mg/kg DCHP dose groups in neonatal male rats. In contrast, for female rats, there was an increase in body weights in the 100-mg/kg DCHP dose group and there was a decrease in body weights in the 500-mg/kg DHP dose group. Body weights were increased at 20 and 500 mg/kg in the DHP-exposed juvenile male rats. Serum thyroid-stimulating hormone (TSH) levels were increased in neonatal male rats, while they were increased in the 100-mg/kg DHP group of neonatal and juvenile female rats. Serum triiodothyronine (T3) levels were increased at the high dose of DHP for neonatal male rats and at the low and high dose levels of DCHP for female rats. Serum thyroxine (T4) levels were increased in neonatal rats for DHP. Also, some histopathological changes were observed in the thyroid, pancreas, adrenal, and pituitary gland. In conclusion, it was shown that DHP and DCHP caused negative effects on T3, T4, and TSH hormone levels.

Effects of intrahypothalamic crystalline steroids on acute ACTH secretion

1963 ◽  
Vol 205 (4) ◽  
pp. 671-673 ◽  
Author(s):  
Israel Chowers ◽  
Shaul Feldman ◽  
Julian M. Davidson
Keyword(s):  
Ascorbic Acid ◽  
Pituitary Gland ◽  
Median Eminence ◽  
Acute Stress ◽  
Testosterone Propionate ◽  
Experimental Period ◽  
Male Rats ◽  
Acth Secretion ◽  
Unilateral Adrenalectomy ◽  
Cortisol Implants

The respective roles of the hypothalamus and pituitary gland, in the inhibition of adrenocorticotropin secretion by corticoids, were studied by implanting small quantities of crystalline cortisol acetate in the median eminence region and pituitary of male rats. Adrenal weights and adrenal ascorbic acid depletion (AAAD) in response to the acute stress of unilateral adrenalectomy were measured 5, 10, 13, or 21 days postoperatively. Ten days following implantation in the hypothalamus, rats showed adrenal atrophy and inhibition of AAAD. Normal AAAD and slight adrenal hypertrophy were found 10 days after similar implantation of testosterone propionate in the median eminence. Animals with cortisol implants in the pituitary had normal adrenal weights and AAAD responses at this time. In rats with cortisol implants in the hypothalamus, an inhibition of AAAD was present after 5–6 days, had increased maximally at 13 days, and returned to normal at 21 days. Adrenal atrophy, however, was first noted at 10 days and adrenal weight continued to decline throughout the experimental period.

Compensatory Adrenal Growth in Immature and Mature Male Rats

1980 ◽  
Vol 31 (1) ◽  
pp. 34-38 ◽  
Author(s):  
Matilde A. Holzwarth ◽  
Charles W. Wilkinson ◽  
Mary F. Dallman
Keyword(s):  
Mature Male ◽  
Male Rats
Sign in / Sign up

Export Citation Format

Share Document