Effects of antihistamines on isolated mast cells from the rat, guinea pig and man.

The effects of a range of antihistamines and related compounds on mast cells from a number of different locations have been investigated. The drugs had a dual action on all the cell types examined: at high concentrations they induced histamine release while at low concentrations they inhibited the secretion of the amine evoked by antigen. The relative potencies of the various compounds in both evoking and preventing histamine release varied from one mast cell to another. In total, these studies then further emphasise the functional heterogeneity of mast cells from different locations.