Cell proliferation in carcinoid valve disease: a mechanism for serotonin effects.

Abstract

Serotonin is a powerful mitogen for valvular subendocardial cells. The mitogenic effect is at least partly mediated via 5HT1b receptors. Subendothelial cell proliferation is significantly elevated in human carcinoid valves in vivo. The data suggest a mechanism whereby serotonin may contribute to valvular proliferation in carcinoid heart disease.