Evidence for basal and stress-induced release of corticotropin releasing factor in the push-pull cannulated median eminence of conscious free-moving rats.
Fourteen adult male rats were successfully implanted in their median eminence with a push-pull cannula perfusing an artificial fluid at a rate of 13 microliters/min, to measure the release of corticotropin releasing factor (rCRF-41) under physiological conditions assessed by baseline plasma adrenocorticotropic hormone (ACTH) levels. In the basal conscious free-moving state, rCRF-41 release displayed a fluctuating pattern, with peaks about every 45 min at a mean value of 9.0 +/- 0.7 pg/15 min sample (n = 42) vs a mean trough value of 4.1 +/- 0.3 pg/sample (n = 44). Ether stress was followed by a striking rise in rCRF-41 release which generally lasted about 45 min and reached mean peak values of 54.3 +/- 3.2 pg/15 min sample (n = 7). These data constitute the first direct measurements of basal and stress-induced CRF releases in conscious unrestrained rats.
D000324:Adrenocorticotropic Hormone / Q000097:blood; D000818:Animals; D002404:Catheterization; D003345:Corticosterone / Q000097:blood; D003346:Corticotropin-Releasing Hormone / Q000378:metabolism*; D004986:Ether; D008297:Male; D008473:Median Eminence / Q000378:metabolism*; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains; D013312:Stress, Physiological / Q000139:chemically induced / Q000378:metabolism*
D004986:Ether; D000324:Adrenocorticotropic Hormone; D003346:Corticotropin-Releasing Hormone; D003345:Corticosterone