The effects of histamine H2-receptor antagonists on PHA induced lymphocyte proliferation.

Histamine H2-receptor antagonists must be used with caution to define the pharmacology of histamine effects on lymphocyte mitogenesis induced by PHA, because they can enhance and/or suppress in their own right, because these effects are similar to those of histamine itself, because mitogenic doses of PHA can release significant amounts of histamine from supposedly pure mononuclear cell preparations.