Evidence for cholecystokininA receptors in bovine adrenal chromaffin cells

We have studied a possible role of cholecystokinin (CCK) in regulating adrenal medullary function. Caerulein (10-10 M), a CCK receptor agonist, increased formation of inositol phosphates in primary cultured bovine adrenal medullary (BAM) chromaffin cells in a concentration-dependent manner. The effect of caerulein was antagonized by devazepide, a selective CCKA-receptor antagonist, but not by L-365.260, a selective CCKB-receptor antagonist. These results suggest that BAM cells possess functional CCK receptors of the CCKA-subtype. Stimulation of these receptors with caerulein activates a signal transduction pathway via phospholipase C. CCK may regulate catecholamine release in BAM cells.