Antiallergic activity of nylidrin hydrochloride (RHC 3432-A). II. A lack of correlation between inhibition of mediator release and levels of cyclic AMP.
Nylidrin hydrochloride has weak beta-adrenergic agonist properties with rat mast cells, and shows synergy with 3-isobutyl-1-methylxanthine (IBMX) in raising intracellular cAMP in purified mast cells; both of these properties can be blocked by dl-propranolol. However, the action of nylidrin hydrochloride as an inhibitor of histamine secretion from purified rat mast cells is not antagonized by dl-propranolol, nor is it potentiated by IBMX. Nylidrin-induced elevation of cellular cAMP in purified rat mast cells shows no correlation with nylidrin-induced inhibition of histamine release. Thus, nylidrin hydrochloride inhibits release of histamine from mast cells by a novel, non-adrenergic mechanism, which is not dependent on increased levels of cAMP.
D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000494:pharmacology; D000242:Cyclic AMP / Q000032:analysis*; D006634:Histamine H1 Antagonists; D006636:Histamine Release; D007073:Immunoglobulin E / Q000276:immunology; D008407:Mast Cells / Q000032:analysis*; D009756:Nylidrin / Q000494:pharmacology*; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
D000888:Antibodies, Anti-Idiotypic; D006634:Histamine H1 Antagonists; D010726:Phosphodiesterase Inhibitors; D007073:Immunoglobulin E; D009756:Nylidrin; D011433:Propranolol; D000242:Cyclic AMP