Immunohistochemical studies on S-100 cells in the anterior pituitary gland of Sprague Dawley rats and spontaneous dwarf rats

1993 ◽  
Vol 188 (5) ◽  
Author(s):  
Toshiaki Watanabe ◽  
Hisashi Hashimoto
1988 ◽  
Vol 118 (2) ◽  
pp. 237-NP ◽  
Author(s):  
A. M. McNicol ◽  
M. A. G. Kubba ◽  
E. McTeague

ABSTRACT The immunohistochemically defined corticotroph population in the anterior pituitary gland of the adult male Sprague–Dawley rat has been quantified at 2 and 6 weeks after bilateral adrenalectomy using the stereological measurement, volume density (Vv). An approximately twofold increase in corticotroph Vv was demonstrated at 2 weeks in adrenalectomized rats compared with that in sham-operated controls and this was maintained at 6 weeks. Daily i.p. injections of ovine corticotrophin-releasing factor (CRF-41) induced a significant dose-related increase in corticotroph Vv when administered at doses of 25 and 50 μg/kg body weight, but this was less than the increase following adrenalectomy. Assessment of changes in mitotic activity of the total anterior lobe of adult Sprague–Dawley rats and of the corticotroph population was also made after daily i.p. injections of 50 μg CRF-41/kg for 2 and 7 days. There was no increase in overall mitotic index at either time. However, the numbers of mitotic corticotrophs were significantly increased in CRF-injected animals compared with those in saline-injected rats. These results indicate a role for CRF-41 in the regulation of corticotroph growth. J. Endocr. (1988) 118, 237–241


2013 ◽  
Vol 115 (11) ◽  
pp. 1641-1647 ◽  
Author(s):  
William J. Kraemer ◽  
Shawn D. Flanagan ◽  
Jeff S. Volek ◽  
Bradley C. Nindl ◽  
Jakob L. Vingren ◽  
...  

The anterior pituitary gland (AP) increases growth hormone (GH) secretion in response to resistance exercise (RE), but the nature of AP adaptations to RE is unknown. To that end, we examined the effects of RE on regional AP somatotroph GH release, structure, and relative quantity. Thirty-six Sprague-Dawley rats were assigned to one of four groups: 1) no training or acute exercise (NT-NEX); 2) no training with acute exercise (NT-EX); 3) resistance training without acute exercise (RT-NEX); 4) resistance training with acute exercise (RT-EX). RE incorporated 10, 1 m-weighted ladder climbs at an 85° angle. RT groups trained 3 days/wk for 7 wk, progressively. After death, trunk blood was collected, and each AP was divided into quadrants (ventral-dorsal and left-right). We measured: 1) trunk plasma GH; 2) somatotroph GH release; 3) somatotroph size; 4) somatotroph secretory content; and 5) percent of AP cells identified as somatotrophs. Trunk GH differed by group (NT-NEX, 8.9 ± 2.4 μg/l; RT-NEX, 9.2 ± 3.5 μg/l; NT-EX, 15.6 ± 3.4 μg/l; RT-EX, 23.4 ± 4.6 μg/l). RT-EX demonstrated greater somatotroph GH release than all other groups, predominantly in ventral regions ( P < 0.05-0.10). Ventral somatotrophs were larger in NT-EX and RT-NEX compared with RT-EX ( P < 0.05–0.10). RT-NEX exhibited significantly greater secretory granule content than all other groups but in the ventral-right region only ( P < 0.05–0.10). Our findings indicate reproducible patterns of spatially distinct, functionally different somatotroph subpopulations in the rat pituitary gland. RE training appears to induce dynamic adaptations in somatotroph structure and function.


1957 ◽  
Vol 189 (1) ◽  
pp. 86-90 ◽  
Author(s):  
Harold A. Levey ◽  
Sidney Roberts

The weight and rate of oxygen consumption of the anterior pituitary gland of the male Sprague-Dawley rat were observed to decline with age. Thyroidectomy, administration of thiouracil or propylthiouracil, and castration significantly elevated pituitary weight, while all but the latter procedure resulted in increased oxygen consumption of this gland. Adrenalectomy was without effect in these respects. Pituitary hypertrophy after thyroidectomy was associated with hyperemia and increased water and protein content. No changes were observed in glucose utilization, lactate production, and levels of succinic dehydrogenase and cytochrome oxidase in the pituitary gland following thyroidectomy. Administration of thyroxine to thyroidectomized rats restored normal pituitary weight and respiratory activity. Diiodothyronine and triiodothyronine were somewhat less effective than thyroxine. Diiodotyrosine and potassium iodide were ineffective. The relationship of pituitary metabolism to protein hormone synthesis in this gland is discussed.


2004 ◽  
Vol 278A (1) ◽  
pp. 462-473 ◽  
Author(s):  
Nobuyuki Shirasawa ◽  
Yoshio Mabuchi ◽  
Eisuke Sakuma ◽  
Osamu Horiuchi ◽  
Takashi Yashiro ◽  
...  

1968 ◽  
Vol 243 (15) ◽  
pp. 4143-4150 ◽  
Author(s):  
J K McDonald ◽  
F H Leibach ◽  
R E Grindeland ◽  
S Ellis

1979 ◽  
Vol 16 (2) ◽  
pp. 99-112 ◽  
Author(s):  
Thérèse Di Paolo ◽  
Réjean Carmichael ◽  
Fernand Labrie ◽  
Jean-Pierre Raynaud

1984 ◽  
Vol 100 (2) ◽  
pp. 219-226 ◽  
Author(s):  
S. A. Nicholson ◽  
T. E. Adrian ◽  
B. Gillham ◽  
M. T. Jones ◽  
S. R. Bloom

ABSTRACT The effect of six hypothalamic peptides on the basal release of ACTH and that induced by arginine vasopressin (AVP) or by ovine corticotrophin releasing factor (oCRF) from fragments of the rat anterior pituitary gland incubated in vitro was investigated. Dose–response curves to AVP and to oCRF were obtained, and the response to a low dose of oCRF was potentiated by a low dose of AVP. Basal release of ACTH was not affected by any of the peptides in concentrations in the range 10−12 to 10−6 mol/l, and only substance P (SP) and somatostatin (SRIF) inhibited significantly the response to oCRF in a dose-related manner. The responses to a range of doses of oCRF or AVP were reduced by 10−8 and 10 − 6 mol SP or SRIF/1, and to a greater extent by the higher dose. Except in the case of 10−6 mol SRIF/1 on the response to AVP, the response was not further diminished by preincubation of the tissue with the peptide before the stimulating agent was added. The inhibition of the responses to AVP or oCRF by 10−9 mol SP/1 was not potentiated by its combination with either 5 × 10−10 or 10−8 mol SRIF/1; the inhibitory effects were merely additive. The results suggest that although SRIF and SP are able to modulate the release of ACTH from the anterior pituitary gland, they do so only at a high concentration. In the case of SRIF these concentrations are several orders of magnitude higher than those reported to be present in the hypophysial portal blood and therefore a physiological role for this peptide in the control of ACTH secretion is unlikely. J. Endocr. (1984) 100, 219–226


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