Lacidipine decreases the honeybee venom-induced vasoconstriction of the isolated porcine coronary artery.

The venom of the honeybee Apis mellifera induces cardiovascular dysfunction. As its effects on coronary arteries have not yet been described, we studied the effects of the whole honeybee venom (non-volatile part) in the isolated porcine left anterior descending coronary artery (LAD) and the influence of L-type Ca2+ channel blocker, lacidipine, upon the venom effects in LAD. The venom produced concentration dependent contractions (7-70 microg/ml) of the porcine LAD; maximal effect of the venom was approximately the same as the effect of 30 mM KCl. Lacidipine concentration dependently (0.1-10 microM) and significantly (P < or = 0.05) decreased the venom-induced vasoconstriction. The results indicate the involvement of L-type Ca2+ channels in coronary contraction, induced by bee venom.