Role of chain termini in selective steroidogenic effect of ACTH/MSH(4-10) on isolated adrenocortical cells.

To investigate the role of charged chain ends in the corticosteroidogenic effect of ACTH/MSH(4-10), acetyl and amide derivatives of ACTH/MSH(4-10) were synthesized and tested in isolated zona glomerulosa and zona fasciculata cells. ACTH/MSH(4-10)-NH2, Ac-ACTH/MSH(4-10) and Ac-ACTH/MSH(4-10)-NH2 (10 microM to 1 mM) stimulated the aldosterone production of zona glomerulosa cells, whereas these peptides did not stimulate the corticosterone production of zona fasciculata cells, even at 1 mM concentration. As ACTH/MSH(4-10) has been shown to have a steroidogenic effect on both types of adrenocortical cells, both charged chain termini seem to be essential for triggering of the corticosterone production of zona fasciculata cells, but for aldosterone production their presence appears not to be important.