Role of Contractile Microfilaments in the Release of Histamine from Mast Cells

THE release of histamine and other mediators of immediate type anaphylactic reactions from mast cells is triggered by the interaction of antigen with cell-bound antibody. Antigen-induced histamine release and that induced by Compound 48/80 are energy-dependent processes which are depressed by metabolic inhibitors and follow a similar time course 1–3 . This type of selective release of histamine is inhibited by the potent anti-asthmatic drug disodium cromoglycate (DSCG) 4 , whereas the non-selective release induced by agents such as the detergent ‘Triton X-100’, which follows a different time course and is not energy dependent, is not blocked by DSCG. It has therefore been postulated 4,5 that histamine is released from mast cells by two distinct mechanisms: a selective release of amine-containing granules through a process of exocytosis, and a non-selective release of amines and other cellular constituents as a result of lysis of cell membranes.