Bäumner D, Nawrath H
Pharmakologisches Institut, Universität Mainz, Germany.
Eur J Pharmacol. 1995 Feb 6;273(3):295-8. doi: 10.1016/0014-2999(94)00752-s.
Several activators of cGMP-dependent protein kinase (protein kinase G) such as 8-Br-cGMP reduced force of contraction in rat left atria. Inhibitors of protein kinase G antagonized the negative inotropic effect of 8-Br-cGMP but not of acetylcholine in atria. However, the acetylcholine-induced relaxation in aortic rings was significantly inhibited by protein kinase G inhibition. It is concluded that the reduction by 8-Br-cGMP of force of contraction in atria is related to activation of protein kinase G. In response to acetylcholine, activation of protein kinase G is probably a major step in smooth muscle relaxation but is not involved in the reduction of force of contraction in atria.
几种环磷酸鸟苷依赖性蛋白激酶（蛋白激酶G）激活剂，如8-溴环磷酸鸟苷，可降低大鼠左心房的收缩力。蛋白激酶G抑制剂可拮抗8-溴环磷酸鸟苷对心房的负性肌力作用，但不能拮抗乙酰胆碱的负性肌力作用。然而，蛋白激酶G抑制可显著抑制乙酰胆碱诱导的主动脉环舒张。结论是，8-溴环磷酸鸟苷降低心房收缩力与蛋白激酶G的激活有关。在乙酰胆碱作用下，蛋白激酶G的激活可能是平滑肌舒张的主要步骤，但不参与心房收缩力的降低。
