THE INOTROPIC ACTIONS OF QUATERNARY AMMONIUM COMPOUNDS

摘要: The cardiac effects of a series quaternary ammonium compounds were studied on the papillary muscle cat and heart-lung preparation dog. Tetramethylammonium displayed muscarinic activity and, after atropine, transitory positive inotropic in both preparations. Tetraethylammonium was devoid effected only responses. Tetra-n-propylammonium produced qualitatively similar to those by tetraethylammonium but less active than latter. Tetra-n-butylammonium caused biphasic response, i.e., an initial effect then negative which not blocked atropine. trimethylethylammonium tetramethylammonium it one-third as Dimethyldiethylammonium inhibited contractility slightly or at all nonatropinized preparations had significant atropinization. Triethylmethylammonium no approached its capacity produce effect. Lower analogues alkyltrimethylammonium, having n-alkyl chains containing up four five carbons, exhibited (maximal butyl derivative) higher muscles. On atropinized muscle, members this being greatest hexyl member. In preparation, alkyltrimethylammonium series, except octyl member, maximal found pentyl hypodynamic heptyl compounds, improved performance. Maximal Octyltrimethylammonium increased contractile amplitude failed preparation. Phenyltrimethylammonium, benzyltrimethylammonium β-phenethyltrimethylammonium evoked marked response more pronounced predominated case phenyl phenethyl whereas benzyltrimethylammonium. However, these analogue most potent. Successive replacement methyl groups ethyl radicals phenyltrimethylammonium enhanced same time resulted decreased duration action. Meta -hydroxylation phenyltrialkylammonium studied.