Regulation of bovine adrenal cell corticotropin receptor mRNA levels by corticotropin (ACTH) and angiotensin-II (A-II).
Bovine adrenal fasciculata-reticularis cells (BAC) expressed at least four ACTH receptor (ACTH-R) mRNA transcripts, one major of 3.6 kb and three minor of 4.2, 1.8 and 1.3 kb. ACTH and A-II increased ACTH-R mRNA levels in a time- and dose-dependent manner. At maximal concentrations, ACTH caused a 2.7-fold increase in the level of the major transcript of 3.6 kb with an ED50 = 10(-11) M and A-II produced a 2.4-fold increase with an ED50 = 5 x 10(-8) M. Under our experimental conditions, the stimulatory effects of both hormones appeared to be due to post-transcriptional changes rather than to transcriptional regulation since the hormonal effects were also observed in actinomycin-treated cells. The results indicate that regulation of ACTH-R mRNA levels may be one mechanism by which ACTH and A-II regulate adrenocortical functions.
INSERM-INRA U.307, Hôpital Debrousse, Lyon, France.
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A
Penhoat
C
C
Jaillard
J M
JM
Saez
D000324:Adrenocorticotropic Hormone / Q000494:pharmacology*; D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D003609:Dactinomycin / Q000494:pharmacology; D005786:Gene Expression Regulation / Q000187:drug effects*; D007700:Kinetics; D012333:RNA, Messenger / Q000378:metabolism*; D018043:Receptors, Corticotropin / Q000235:genetics*; D015383:Zona Fasciculata / Q000378:metabolism*
D012333:RNA, Messenger; D018043:Receptors, Corticotropin; D000804:Angiotensin II; D003609:Dactinomycin; D000324:Adrenocorticotropic Hormone