NEONATAL CORTICOID ADMINISTRATION: EFFECTS UPON ADULT PITUITARY GROWTH HORMONE AND HYPOTHALAMIC GROWTH HORMONE-RELEASING HORMONE ACTIVITY

1969 ◽  
Vol 61 (1) ◽  
pp. 57-67 ◽  
Author(s):  
Shinji Sawano ◽  
Akira Arimura ◽  
Andrew V. Schally ◽  
Tommie W. Redding ◽  
Shawn Schapiro
Keyword(s):  
Growth Hormone ◽  
Growth Retardation ◽  
Subcutaneous Injection ◽  
Growth Hormone Releasing Hormone ◽  
Hormone Activity ◽  
Single Subcutaneous Injection ◽  
Releasing Hormone ◽  
Pituitary Growth Hormone

ABSTRACT A single subcutaneous injection of 1 mg cortisone or cortisol acetate was given to rats during the first post-natal day. As others have reported, retardation of growth, detectable a week after birth, resulted. On reaching five to six weeks of age, treated rats had no detectable growth hormone (GH)-releasing activity in their hypothalami and little GH or thyrotrophin (TSH) activity in their pituitaries. These observations suggest that the growth retardation of rats treated neonatally with these steroids may be due, at least in part, to lack of pituitary GH resulting from impaired synthesis of GH-releasing hormone (GRH**) and also to lack of TSH.

5-α androstane diol stimulates the pituitary growth hormone responsiveness to growth hormone releasing hormone more effectively than testosterone or dihydrotestosterone in rats

1992 ◽  
Vol 126 (2) ◽  
pp. 162-166 ◽  
Author(s):  
E Aguilar ◽  
M Tena-Sempere ◽  
L Pinilla
Keyword(s):  
Growth Hormone ◽  
Hormone Secretion ◽  
Plasma Concentrations ◽  
Growth Hormone Secretion ◽  
Growth Hormone Releasing Hormone ◽  
Releasing Hormone ◽  
Pituitary Growth Hormone ◽  
Hormone Content ◽  
Anaesthetized Rats ◽  
Male Wistar Rats

The effect of different androgens and estradiol on pituitary responsiveness to growth hormone releasing hormone was studied in intact and orchidectomized adult male Wistar rats, by injecting subcutaneously immediately after orchidectomy for two weeks with testosterone, dihydrotestosterone, 5-α androstane, 3-α, 17 β-diol or estradiol dissolved in olive oil (in doses of 0.2 or 2.0 mg·kg−1·day−1) or vehicle. Pituitary responsiveness was tested in pentobarbital anaesthetized rats by measuring growth hormone plasma levels at different times after administration of growth hormone releasing hormone (1-29) NH2. We found that: (a) High doses of testosterone, dihydrotestosterone and 5-α androstane, 3α, 1 7 β-diol restored gonadotropin plasma concentrations and organ weights altered by orchidectomy; (b) both pituitary growth hormone content and concentration remained unaffected after orchidectomy or androgen replacement and decreased significantly after estradiol injection; (c) orchidectomy significantly reduced growth hormone-stimulated growth hormone releasing hormone secretion; (d) treatment with 5-α androstane, 3-α, 1 7 β-diol increased more than testosterone or dihydrotestosterone both the peak concentration and the mean growth hormone secretion after growth hormone releasing hormone stimulation: (e) no differences were observed in the treatment with testosterone or dihydrotestosterone; (f) estradiol given at a dose of 0.2 mg·kg−1·day−1 increased pituitary responsiveness to growth hormone releasing hormone. These results demonstrated that testosterone and 5-α androstane, 3-α, 17 β-diol, which do not differ in their action on pituitary growth hormone content, increased the pituitary responsiveness to growth hormone releasing hormone differently and that the low pituitary responsiveness to growth hormone releasing hormone previously described in prepubertal animals was not due mainly to the secretion of 5-α androstane, 3-α, 1 7 β-diol.

Ectopic Acromegaly: Localization of the Pituitary Growth Hormone-Releasing Hormone Producing Tumor by In-111 Pentetreotide Scintigraphy and Report of Two Cases

2004 ◽  
Vol 29 (12) ◽  
pp. 841-843 ◽  
Author(s):  
Olivier Morel ◽  
Philippe Giraud ◽  
Marie-Odile Bernier ◽  
Jean-Jacques Le Jeune ◽  
Vincent Rohmer ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Growth Hormone Releasing Hormone ◽  
Releasing Hormone ◽  
Pituitary Growth Hormone ◽  
Ectopic Acromegaly
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