盐酸菲洛普消旋体和左旋体对钙及α_1肾上腺素受体拮抗作用强度的比较

Comparison of the Blocking Effects of 1-(2,6-dimethylphenoxy) -2-(3,4-dimeth Oxyphenylethylamino) Propane Hydrochloride (DDPH) and Its (-) Enantiomers on Calcium Channel and α_1-Adrenoreceptor

比较 1- (2 ,6 -二甲基苯氧基 ) - 2 - (3,4-二甲氧基苯乙胺基 )丙烷盐酸盐 (盐酸菲洛普 ,DDPH)消旋体和左旋体的钙拮抗作用及 α1 肾上腺素受体阻断作用强度。采用全细胞膜片钳记录单个豚鼠心室肌细胞的钙电流 ,兔离体主动脉条实验绘制氯化钙和去氧肾上腺素量效关系曲线。结果发现 :(± ) DDPH和 (- ) DDPH剂量依赖性地阻断豚鼠心室肌细胞钙电流 ,其 IC50 分别为 2 2 .5 μmol/ L (n=8)和 16 .7μmol/ L (n=10 )。 (± ) DDPH和 (- ) DDPH使 Ca Cl2量效关系曲线右移 ,最大效应降低 ;使去氧肾上腺素量效关系曲线平行右移 ,最大效应不变。提示 :DDPH(± )和 DDPH(- )的钙拮抗作用及 α1 肾上腺素受体阻断作用强度无统计学差异。

The blocking effects of 1 (2,6 dimethylphenoxy) 2 (3,4 dimethoxyphenylethylamino) propane hydrochloride (DDPH) and its (-) enantiomers on calcium channel and α 1 adrenoceptor were investigated. Whole cell patch clamp was used to record calcium current in single isolated ventricle cells of guinea pig. The concentration response curve of CaCl 2 or phenylephrine (Phe) were recorded in the isolated rabbit thoratic aorta. The results showed that (±) DDPH and (-) DDPH decreased L type calcium current (L ) significantly in a concentration dependent manner with the IC 50 values being 22 5 μmol/L ( n =8) and 16 7 μmol/L ( n =10) respectively. (±) DDPH and (-) DDPH made CaCl 2 concentration response curves move to the right, and reduced the maximal contractile force. DDPH and (-) DDPH caused parallel rightward shifts of the Phe induced concentration response curves, but didn't suppress the maximal contractile respose to Phe. The data suggested that (±)DDPH and (-) DDPH exerted equal calcium antagonistic action and α 1 adrenoceptor blocking effect.