A protective action of disodium cromoglycate against the contraction of guinea-pig ileum induced by various pharmacological stimulants.

The effect of disodium cromoglycate (DSCG) on the contraction of isolated guinea-pig ileum induced by histamine, acetylcholine and serotonin has been investigated. DSCG protected ileum against all agents tested. The action of DSCG at concentrations of 10(-3) to 10(-2) M was both dose- and time-dependent. Furthermore, DSCG inhibited compound 48/80-induced histamine release from isolated mast cells over the same range of concentrations. The anti-histaminic action of DSCG was reversible and after 2 h the ileum responded normally to histamine. DSCG-induced inhibition of the contractile response to histamine could be overcome by increasing concentrations of histamine but not by extracellular calcium. A mechanism of the action of DSCG, either against the contraction of ileal smooth muscle or against histamine release from mast cells, is discussed with a view to the inhibition of the utilization of calcium ions by both cells.