Adrenocortical ACTH receptors in pigs of differing in vivo response to adrenocorticotropin.
1. Adrenocortical membrane protein was isolated from the adrenal glands of 12 Large White x Landrace male pigs, six with high adrenocortical response to adrenocorticotropic hormone (ACTH) and six with low response. 2. The peptide (Phe2, Nle4) ACTH was iodinated by the chloramine-T method and served as the radioligand in receptor binding studies. 3. Only one class of ACTH receptor was detected, with Kd = 2.57 +/- 0.35 x 10(9) M and Bmax = 1.59 +/- 0.06 pmol/mg protein in high responders and Kd = 1.68 +/- 0.18 x 10(-9) M and Bmax = 1.17 +/- 0.11 pmol/mg protein in low responders. 4. The difference in the Bmax between high and low responders was significant (P < 0.05), the difference in Kd was not statistically significant.
Zhang
S H
SH
School of Agriculture, La Trobe University, Bundoora, Victoria, Australia.
Hennessy
D P
DP
McCauley
I
I
Cranwell
P D
PD
D000302:Adrenal Cortex / Q000187:drug effects / Q000378:metabolism*; D000324:Adrenocorticotropic Hormone / Q000008:administration & dosage* / Q000031:analogs & derivatives / Q000493:pharmacokinetics; D000818:Animals; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D003366:Cosyntropin / Q000031:analogs & derivatives / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D007668:Kidney / Q000187:drug effects / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008565:Membrane Proteins / Q000494:pharmacology; D011485:Protein Binding / Q000187:drug effects; D018043:Receptors, Corticotropin; D011979:Receptors, Pituitary Hormone / Q000187:drug effects* / Q000378:metabolism*; D013552:Swine; D013997:Time Factors
D008565:Membrane Proteins; D018043:Receptors, Corticotropin; D011979:Receptors, Pituitary Hormone; D003366:Cosyntropin; D000324:Adrenocorticotropic Hormone; C045739:ACTH (1-24), Phe(2)-Nle(4)-