Endothelin stimulates aldosterone biosynthesis by dispersed rabbit adreno-capsular cells

The effect of endothelin on aldosterone production by dispersed adreno-capsular cells from rabbits was examined. Porcine endothelin stimulated aldosterone production dose-dependently with an EC50 of 5 x 10(-14) M, but had no effect on corticosterone production. A calcium channel blocker, nicardipine, completely inhibited the stimulatory effect of endothelin on aldosterone production. Endothelin induced prompt and sustained increase in intracellular Ca2+ in fura-2-loaded cells, and nicardipine inhibited this increase in intracellular Ca2+. These results indicate that endothelin stimulates aldosterone biosynthesis in dispersed zona glomerulosa cells of rabbits, and that its effects is related to increase in intracellular calcium through voltage-dependent calcium channels.