Ivermectin as an inhibitor of the plasma membrane and the sarcoplasmic/endoplasmic reticulum Ca2+-ATPases in rat vas deferens

Abstract

ObjectiveThe present work investigated the effect of ivermectin on Ca2+ content and on the Ca2+-ATPase activity (represented by the plasma membrane Ca2+-ATPase and the sarcoplasmic/endoplasmic reticulum Ca2+-ATPase present in rat vas deferens.MethodsThe assays were carried out using ultracentrifuged homogenate preparations from rat vas deferens in the presence or absence of the 12-kDa FK506-binding protein-Ca2+ release channel complex. Measures of Ca2+ content and Ca2+ ATPase activity were then carried out in function of different concentrations of ivermectin. ResultsThe data show that ivermectin (10 μM) reduces the sarcoplasmic reticulum Ca2+ content in FK506-binding protein (+) and FK506-binding protein (-) fractions of ultracentrifuged homogenate from rat vas deferens (inhibition of 50% and 40%, respectively, p<0.05) and inhibits both the activities of sarcoplasmic/endoplasmic reticulum Ca2+-ATPase and plasma membrane Ca2+-ATPases pumps (33% and 16%, respectively, p<0.05).ConclusionThese data suggest that ivermectin effects Ca2+ handling in the rat vas deferens, indicating that this drug could alter the contractility of this smooth muscle. Therefore, ivermectin could be an interesting pharmacological tool to alter the physiological function of vas deferens and to manipulate the fertility status of male rats.Indexing terms: Calcium. Ivermectin. Rats.