Inhibition of allergic and non-allergic histamine secretion from rat peritoneal mast cells by calcium antagonists.
Bepridil, TMB-8 (8-(diethylamino)octyl 3,4,5-trimethoxybenzoate hydrochloride), diltiazem, verapamil and nifedipine exerted concentration-dependent inhibition of antigen and calcium ionophore A23187-induced histamine release from rat peritoneal mast cells. The inhibitory effects of verapamil and bepridil against calcium ionophore A23187-induced histamine secretion were antagonized by increased Ca2+ concentrations in the extracellular medium. These observations suggest that both agents act by interfering with the influx of Ca2+ into the mast cells. The inhibitory activities of five different Ca2+ channel blockers on allergic and non-allergic histamine secretion from rat peritoneal mast cells varied considerably depending upon the nature of the secretagogue as well as concentration and type of Ca2+-antagonist examined.
D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D006636:Histamine Release / Q000187:drug effects*; D006967:Hypersensitivity / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D008407:Mast Cells / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
D002121:Calcium Channel Blockers; D002118:Calcium