Fernandez A I, Cantabrana B, Hidalgo A
Departamento de Medicina, Facultad de Medicina, Oviedo, Spain.
Pharmacology. 1993 Sep;47(3):152-7. doi: 10.1159/000139092.
The effect of the activator, phorbol 12,13-dibutyrate (PDB), and the inhibitor, H-7, of protein kinase C (PKC) has been assayed in rat uterus. PDB increases the amplitude of spontaneous contractions of rat uterus and this effect does not occur in the presence of H-7 or nifedipine. PDB did not modify the KCl-induced tonic contraction but H-7 relaxed it, in a concentration-dependent way. PDB inhibited the contraction induced by oxytocin in rat uterus incubated in Ca-free solution and relaxed the tonic contraction induced by oxytocin in this medium. The relaxing effect of PDB on oxytocin-induced contraction was not modified by H-7. Thus H-7 relaxed, in a concentration-dependent way, the tonic contractions induced by oxytocin and vanadate in the rat uterus incubated in Ca-free medium. Our results suggest a dual effect of PDB related to calcium, and a direct and PKC-independent inhibitory effect of H-7.
已在大鼠子宫中检测了蛋白激酶C（PKC）的激活剂佛波醇12,13 - 二丁酸酯（PDB）和抑制剂H - 7的作用。PDB增加大鼠子宫自发收缩的幅度，而在存在H - 7或硝苯地平的情况下这种作用不会发生。PDB未改变氯化钾诱导的强直性收缩，但H - 7以浓度依赖的方式使其松弛。PDB抑制无钙溶液中孵育的大鼠子宫由催产素诱导的收缩，并使该培养基中由催产素诱导的强直性收缩松弛。PDB对催产素诱导收缩的松弛作用未被H - 7改变。因此，H - 7以浓度依赖的方式使无钙培养基中孵育的大鼠子宫由催产素和钒酸盐诱导的强直性收缩松弛。我们的结果表明PDB与钙有关的双重作用，以及H - 7的直接且不依赖PKC的抑制作用。
