Muscarinic M2 receptors in bovine tracheal smooth muscle: discrepancies between binding and function

摘要: Previous work showing that AF-DX 116, a cardioselective muscarinic antagonist in functional experiments, does not discriminate between receptors bovine cardiac and tracheal membranes has been extended. In addition to 116 we used the antagonists, atropine, pirenzepine, 4-DAMP methobromide, gallamine, hexahydrosiladifenidol methoctramine, radioligand binding experiments on left ventricular smooth muscle membranes. The antagonism of methacholine-induced contraction strips was also evaluated. An excellent correlation found for all compounds affinities membranes; moreover, correspond with pA2 values reported atrial preparations rat guinea pig. However, significant occasionally marked discrepancies were these antagonists muscle.