Disodium cromoglycate inhibition of substance P-induced histamine secretion is calcium dependent.
Histamine secretion was induced by substance P, in a dose-dependent manner, from rat peritoneal mast cells, both in the presence and absence of Ca2+ in the medium, and disodium cromoglycate (DSCG) produced a dose-dependent inhibition of the histamine secretion in Ca2+-containing medium. However, in the absence of Ca2+, DSCG was ineffective or had a far weaker activity. Mg2+, Sr2+ and Ba2+ were ineffective in restoring the DSCG activity when added to medium devoid of divalent metal ions. Therefore, extracellular Ca2+ seems to be a specific requirement for the binding of DSCG to its "receptors" on the mast cell surface or some steps in the DSCG action.
D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D004205:Cromolyn Sodium / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D006636:Histamine Release / Q000187:drug effects*; D066298:In Vitro Techniques; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013373:Substance P / Q000494:pharmacology*
D013373:Substance P; D004205:Cromolyn Sodium; D002118:Calcium