Adrenocorticotropic hormone and cortisol response to corticotropin-releasing factor and lysine vasopressin in pigs.
Two experiments were conducted to evaluate the ability of corticotropin-releasing factor (CRF) and lysine vasopressin (LVP) to stimulate the secretion of ACTH and cortisol in pigs. In Exp. 1, barrows were blocked by weight (average BW 97 +/- 1 kg) and received an i.v. bolus of 10 (n = 4), 50 (n = 4), or 100 (n = 3) micrograms of LVP. Samples of plasma were obtained at 10-min intervals for 2 h before and for 2 h after peptide treatment. The percentage of change in plasma concentration of ACTH (average of the concentration 1 h after LVP compared with the average of the 1 h before LVP) was greater (P < .001) for 100 micrograms (452.3 +/- 4.7%) than for 10 (81.5 +/- 5.7%) or 50 micrograms (233.6 +/- 11.3%). Furthermore, the ACTH response was greater (P < .001) to 50 micrograms than to 10 micrograms. The cortisol responses to treatment (average of the concentration 2 h after LVP compared to the average of the 2 h before LVP) were similar in pigs given 50 (132.8 +/- 5.3%) and 100 (123.2 +/- 2.4%) micrograms, but both were greater (P < .001) than the response to 10 micrograms (38.2 +/- 1.4%). In Exp. 2, a dose of LVP was chosen that provided a total mass of peptide similar to the lowest dose in Exp. 1, but this time the peptide was administered at .11 nmol/kg BW. This dose of LVP was chosen because it resulted in neither maximum ACTH nor cortisol secretion in Exp. 1.(ABSTRACT TRUNCATED AT 250 WORDS)
Department of Animal Sciences and Industry, Kansas State University, Manhattan 66506-0201.
J E
JE
Minton
K M
KM
Parsons
D000324:Adrenocorticotropic Hormone / Q000097:blood / Q000378:metabolism*; D000818:Animals; D003346:Corticotropin-Releasing Hormone / Q000494:pharmacology*; D006854:Hydrocortisone / Q000097:blood / Q000378:metabolism*; D008236:Lypressin / Q000494:pharmacology*; D008297:Male; D010913:Pituitary-Adrenal System / Q000187:drug effects / Q000378:metabolism; D013552:Swine / Q000097:blood / Q000378:metabolism*
D008236:Lypressin; D000324:Adrenocorticotropic Hormone; D003346:Corticotropin-Releasing Hormone; D006854:Hydrocortisone