Electrophysiological properties of neurons of guinea pig celiac ganglia

Abstract

The present study was carried out to investigate electrophysiological properties of neurons of guinea pig celiac ganglia in vitro. The mean value of resting membrane potential was-59.3 ±5.6 mV (n = 29). The mean values of membrane resistance, time constant and membrane capacity were 53.7±19.8mΩ, 18.4±8.5 ms, and 375.9±175.0 pF (n = 24) respectively. When depolarizing electrotonic potentials induced by application of depolarizing current pulses reached the threshold level, all of the neurons could be made to discharge action potentials. The mean values of amplitude, overshoot, duration of the spikes were 68.0±15.3 mV, 11.7 ±4.6mV, and 2.7±0.6ms (n = 29) respectively. 75% of the neurons tested (n = 29) produced tonic (slow adapting) firing in response to depolarizing current lasting 5 s. The remaining neurons (25%) produced phasic (fast adapting) firing. In addition, fast excitatory postsynaptic potentials or orihodromic action potentials were recorded from 80% of the neurons, antidromic action potentials were recorded from ihe remaining neurons during stimulation of the splanchnic nerves.

Keywords

electrophysiological property / neuron / sympathetic ganglion / guinea pig

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