Sigma-1 receptor agonist amitriptyline inhibits store-dependent Ca2+ entry in macrophages

Using Fura-2AM microfluorimetry we have shown for the first time that sigma-1 receptor agonist - tricyclic antidepressant amitriptyline - significantly inhibits store-dependent Ca 2+ entry, induced by endoplasmic Ca 2+ -ATPase inhibitors thapsigargin and cyclopiazonic acid, in rat peritoneal macrophages. The results suggest possible involvement of sigma-1 receptors in the regulation of store-dependent Ca 2+ entry in macrophages.