In vitro study of immunoreactive corticotropin-releasing factor release from the rat hypothalamus.
Immunoreactive corticotropin-releasing factor (I-CRF) release from rat hypothalami was studied in vitro utilizing a perifusion of rat hypothalami and a rat CRF RIA. Basal release of I-CRF from the hypothalamus of adrenalectomized or hypophysectomized rats was higher than in that of normal rats. K+-induced I-CRF release was completely suppressed by omission of Ca++ from the medium. Dexamethasone suppressed I-CRF release from hypothalami, but not from median eminence (ME). C-AMP and angiotensin II had mild stimulatory effects on I-CRF release. These results suggest that 1) the feedback mechanism acts mainly on a higher level than ME, and 2) c-AMP and angiotensin II may be involved in CRF-releasing mechanism(s).
D000315:Adrenalectomy; D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000494:pharmacology; D003346:Corticotropin-Releasing Hormone / Q000378:metabolism*; D000242:Cyclic AMP / Q000494:pharmacology; D003907:Dexamethasone / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D007016:Hypophysectomy; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D008473:Median Eminence / Q000187:drug effects / Q000378:metabolism; D011188:Potassium / Q000494:pharmacology; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains
D000804:Angiotensin II; D003907:Dexamethasone; D003346:Corticotropin-Releasing Hormone; D000242:Cyclic AMP; D011188:Potassium; D002118:Calcium