Corticotropin-Releasing Factor Secretion Increases in Rat Hypophysial Portal Blood during Insulin-Induced Hypoglycemia

1989 ◽  
Vol 49 (6) ◽  
pp. 676-679 ◽  
Author(s):  
Viviane Guillaume ◽  
Michel Grino ◽  
Bernard Conte-Devolx ◽  
Françoise Boudouresque ◽  
Charles Oliver
Keyword(s):  
Corticotropin Releasing Factor ◽  
Portal Blood ◽  
Factor Secretion ◽  
Hypophysial Portal

The Corticotropin-Releasing Factor Release in Rat Hypophysial Portal Blood Is Mediated by Brain Catecholamines

1987 ◽  
Vol 46 (2) ◽  
pp. 143-146 ◽  
Author(s):  
Viviane Guillaume ◽  
Bernard Conte-Devolx ◽  
Alain Szafarczyk ◽  
Francis Malaval ◽  
Nicole Pares-Herbute ◽  
...  
Keyword(s):  
Corticotropin Releasing Factor ◽  
Portal Blood ◽  
Brain Catecholamines ◽  
Hypophysial Portal ◽  
Factor Release

Effects of metyrapone infusion on corticotropin-releasing factor and arginine vasopressin secretion into the hypophysial portal blood of conscious, unrestrained rams

1992 ◽  
Vol 127 (5) ◽  
pp. 435-440 ◽  
Author(s):  
B Conte-Devolx ◽  
V Guillaume ◽  
F Boudouresque ◽  
N Graziani ◽  
E Magnan ◽  
...  
Keyword(s):  
Arginine Vasopressin ◽  
Corticotropin Releasing Factor ◽  
Portal Blood ◽  
Moderate Increase ◽  
Acth Secretion ◽  
Tenfold Increase ◽  
Rapid Changes ◽  
Vasopressin Secretion ◽  
Large Increment ◽  
Hypophysial Portal

The effects of rapid changes of circulating cortisol levels on ACTH secretion and on corticotropin-releasing factor (CRF) and arginine vasopressin (AVP) concentrations into hypophysial portal blood were studied in six adult rams. Pharmacological adrenalectomy was obtained by 3 h metyrapone infusion (100 mg·kg−1·h−1). Blockade of cortisol synthesis induced a tenfold increase of plasma ACTH levels accompanied by a moderate increase of CRF secretion (150% vs preinjection levels) and a large increment of AVP secretion (535% vs preinjection levels). ACTH levels remained high during the 3 h following the end of metyrapone infusion. During the same period, CRF secretion was still elevated (231% vs preinjection levels), while AVP secretion was further stimulated (2,151% vs preinjection levels). Subsequent hydrocortisone infusion (66 μg·kg−1·h−1) for 2 h induced a rapid decrease of both ACTH and AVP secretion, while CRF levels in hypophysial portal blood still remained elevated. These data suggest that changes in ACTH secretion induced by acute modifications of the negative glucocorticoid feedback are, in addition to the well documented direct effect of cortisol on the corticotropes, mainly mediated by variations of hypothalamic AVP secretion.

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