An analysis of excitatory junctional potentials recorded from arterioles.

Abstract

Arterioles [guinea pig] were impaled with 2 independent micro-electrodes, one to pass current and the other to record membrane potential. When current was injected into one branch of an arteriole, a membrane potential change could be detected either in the same branch or in an adjoining branch indicating that the arteriolar smooth muscle cells were electrically connected. Fine dissection of the arteriolar tree gave short segments of arteriole which appeared to behave electrically as short cables with sealed ends. Analysis of the electrotonic potentials recorded from isolated segments of arterioles allowed a determination of the arteriole cable properties. According to the cable analyses the junctional current underlying an excitatory junction potential has a brief duration when compared with that of the potential.