Kohl C, Schmitz W, Scholz H, Scholz J, Tóth M, Döring V, Kalmár P
Abteilung Allgemeine Pharmakologie, Universitäts-Krankenhaus Eppendorf, Universität Hamburg, Federal Republic of Germany.
J Cardiovasc Pharmacol. 1989 Feb;13(2):324-7. doi: 10.1097/00005344-198902000-00023.
In human-isolated ventricular myocardium the alpha 1-adrenoceptor agonist phenylephrine has a positive inotropic effect but its mechanism is largely unknown. We studied the effects of phenylephrine in trabeculae isolated from three nonfailing human hearts. We found that the force of contraction rose concentration-dependently (1-300 mumol/L), maximally, to about 235% of control (at 100 mumol/L). The inositol phosphates were increased to 195-262%, whereas the phosphatidylinositol phosphate and phosphatidylinositol bisphosphate decreased to 69-73% of control. The present results suggest that the alpha 1-adrenoceptor-mediated increase in inositol trisphosphate and the positive inotropic effect may be causally related in the normal human heart.
在人离体心室肌中，α1肾上腺素能受体激动剂去氧肾上腺素具有正性肌力作用，但其机制尚不清楚。我们研究了去氧肾上腺素对取自三颗非衰竭人心脏的小梁的作用。我们发现收缩力呈浓度依赖性升高（1 - 300 μmol/L），最大升高至对照的约235%（在100 μmol/L时）。肌醇磷酸增加至195 - 262%，而磷脂酰肌醇磷酸和磷脂酰肌醇二磷酸降至对照的69 - 73%。目前的结果表明，在正常人心脏中，α1肾上腺素能受体介导的肌醇三磷酸增加与正性肌力作用可能存在因果关系。
