Demonstration of histamine H 2 receptors on human melanoma cells

Abstract

Histamine induced a concentration-dependent increase in intracellular cyclic-AMP of the two human melanoma cell lines SK23 and DX3.LT5.1; maximal stimulation was obtained with 17.8μM histamine which consistently produced greater than 50-fold increases in the cyclic AMP content of both cell lines. The dose-response curve for histamine in each culture was progressively displaced to the right with increasing concentrations of the histamine H 2 receptor antagonist cimetidine. Ranitidine, another H 2 receptor antagonist also prevented the histamine-induced cyclic AMP elevation, but the H 1 receptor antagonists mepyramine and tripelennamine had no significant effect. These findings indicate that human melanoma cells express histamine H 2 receptors, stimulation of which activates adenylate cyclase with a subsequent rise in intracellular cyclic AMP. Mast cell:melanoma interactions mediated by histamine in vivo might therefore be expected to modify some aspects of melanoma cell behaviour.