A Study of the Effects of Chlorpromazine on Rat Peripheral Nerves

Abstract

The present study was undertaken to determine the problem of the
nerve fiber-size dependence of the nerve-blocking concentrations of
chlorpromazine, using two types of myelinated nerves, sciatic and phrenic
nerves of the rat; and to compare the blocking concentrations of the drug
with those found in the plasma of the schizophrenic patients. The results
showed that chlorpromazine significantly reduced the amplitude of the
evoked action potential of the isolated rat sciatic nerves, recorded with
extracellular electrodes. The latent period in these nerves was prolonged
indicating lower conduction velocity than the control ones. The depressant
action of chlorpromazine on the ampiitude of the compound action potential
was reversible and dose-dependent. The concentrations required to block
the rat phrenic nerves were about 10-fold lower than those for rat sciatic
nerves and were higher than those found in the plasma of the schizophrenic
patients.