Bimatoprost and its free acid are prostaglandin FP receptor agonists

Bimatoprost (17-phenyl-prostaglandin F-2 alpha ethyl amide) has been reported not to exert its actions via prostaglandin receptors. Here, bimatoprost displaced [H-3]prostaglandin F-2 alpha from FP receptors (K-i = 6310 +/- 1650 nM). Bimatoprost rapidly mobilized intracellular Ca2+ ([Ca2+](i)) via cloned human FP receptors expressed in human embryonic kidney cells (EC50 = 2940 +/- 1663 nM) and via native FP receptors in 3T3 mouse fibroblasts (EC50 = 2200 +/- 670 nM). Furthermore, AL-8810 ((5Z, 13E)-(9S,11S,15R)-9,15-dihydroxy-11-fluoro-15-(2-indanyl)-16,17,18,19,20-pentanor-5,13-prostadienoic acid), an FP receptor antagonist, blocked the bimatoprost-induced [Ca2+](i) mobilization, (C) 2001 Elsevier Science B.V. All rights reserved.