Tomaselli G F, Feldman A M, Yellen G, Marban E
Department of Medicine, Howard Hughes Medical Institute, Johns Hopkins School of Medicine, Baltimore, Maryland 21205.
Am J Physiol. 1990 Mar;258(3 Pt 2):H903-6. doi: 10.1152/ajpheart.1990.258.3.H903.
We report the expression of voltage-dependent Na+ channels in Xenopus oocytes injected with total RNA isolated from explanted human hearts. The expressed channels demonstrate characteristic voltage-dependent gating, inhibition by tetrodotoxin, and selectivity for Na+. Oocytes injected with sterile water or intentionally degraded RNA had no similar channel activity. The antiarrhythmic agent lidocaine (20 microM) inhibits current flow through the channel in a voltage-dependent fashion. Na+ channels expressed by injection of human cardiac RNA into Xenopus oocytes qualitatively resemble channels in the native tissue.
我们报道了在注射从离体人心脏分离的总RNA的非洲爪蟾卵母细胞中电压依赖性钠离子通道的表达。所表达的通道表现出典型的电压依赖性门控、河豚毒素抑制作用以及对钠离子的选择性。注射无菌水或故意降解的RNA的卵母细胞没有类似的通道活性。抗心律失常药物利多卡因(20微摩尔)以电压依赖性方式抑制通过该通道的电流。将人心脏RNA注射到非洲爪蟾卵母细胞中所表达的钠离子通道在性质上类似于天然组织中的通道。