Subclassification of beta-adrenoceptors responsible for steroidogenesis in primary cultures of bovine adrenocortical zona fasciculata/reticularis cells.
1. Forty eight hour primary cultures of purified bovine adrenocortical zona fasciculata/reticularis cells secreted hydrocortisone in response to stimulation with beta-adrenoceptor agonists. The observed order of potency was isoprenaline greater than noradrenaline greater than dobutamine greater than salbutamol greater than BRL37344. 2. Salbutamol acted as a partial agonist on these cells hence suggesting the presence of a beta 1-adrenoceptor. 3. Schild analysis of the hydrocortisone response to isoprenaline showed that the selective beta 1-antagonist practolol and the selective beta 2-antagonist ICI118,551 gave pA2 values of 6.85 and 7.17, respectively. These values were in close agreement with corresponding pA2 values previously obtained for the beta 1-adrenoceptor. 4. We conclude that beta 1-adrenoceptors are responsible for mediating catecholamine-stimulated hydrocortisone secretion from primary cultures of bovine zona fasciculata/reticularis cells.
Lightly
E R
ER
Department of Clinical Chemistry, University of Edinburgh, Royal Infirmary.
Walker
S W
SW
Bird
I M
IM
Williams
B C
BC
D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D002417:Cattle; D002478:Cells, Cultured; D006854:Hydrocortisone / Q000494:pharmacology; D011217:Practolol / Q000494:pharmacology; D011412:Propanolamines / Q000494:pharmacology; D011863:Radioimmunoassay; D011943:Receptors, Adrenergic, beta / Q000187:drug effects*; D013256:Steroids / Q000096:biosynthesis*; D015383:Zona Fasciculata / Q000166:cytology / Q000378:metabolism*; D015385:Zona Reticularis / Q000166:cytology / Q000378:metabolism*
D000318:Adrenergic beta-Agonists; D000319:Adrenergic beta-Antagonists; D011412:Propanolamines; D011943:Receptors, Adrenergic, beta; D013256:Steroids; C026777:ICI 118551; D011217:Practolol; D006854:Hydrocortisone