Baskakov M B, Studnitskiĭ V B, Medvedev M A, Khodorov B I
Biull Eksp Biol Med. 1987 Jul;104(7):8-11.
The effects of protein kinase C activation by 12-O-tetra-decanoyl-phorbol-13-acetate (TPA) on the functions of guinea-pig smooth muscle taenia coli have been studied, using double-sucrose-gap method. A 15-20-min treatment of the muscle with 2 X 10(-8) M TPA caused a progressing inhibition of spontaneous electrical activity and mechanical tension, suppression of post-hyperpolarizing electrical and contractile "off-responses", a decrease in the number of action potentials during superthreshold membrane depolarization, depression of electrical and mechanical responses induced by acetylcholine, histamine, bradykinin mediators. The treatment of pre-depolarized (140 mM kappa+) muscle with 2.10(-8) TPA has led to a considerable reduction in contractile responses induced by the above mediators. The results obtained indicate that protein kinase C is capable of regulating both voltage-sensitive and receptor-operated ionic channels in smooth muscle cells.
采用双蔗糖间隙法研究了12 - O - 十四烷酰佛波醇 - 13 - 乙酸酯（TPA）激活蛋白激酶C对豚鼠平滑肌结肠带功能的影响。用2×10⁻⁸ M TPA处理肌肉15 - 20分钟，可导致自发电活动和机械张力逐渐受到抑制，超极化后电和收缩“关闭反应”受到抑制，阈上膜去极化期间动作电位数量减少，乙酰胆碱、组胺、缓激肽介质诱导的电和机械反应受到抑制。用2×10⁻⁸ TPA处理预去极化（140 mM κ⁺）的肌肉，可导致上述介质诱导的收缩反应显著降低。所得结果表明，蛋白激酶C能够调节平滑肌细胞中的电压敏感型和受体操纵型离子通道。
