Y. Matsumoto et al., EFFECTS OF CARBAMAZEPINE ON NERVE ACTIVITY AND TRANSMITTER RELEASE INNEUROBLASTOMA-GLIOMA HYBRID-CELLS AND THE FROG NEUROMUSCULAR-JUNCTION, Cell biology and toxicology, 14(3), 1998, pp. 191-198
Effects of the antiepileptic drug carbamazepine on nerve action potent
ial and transmitter release in mouse neuroblastoma-glioma hybrid cells
(NG108-15) and the frog neuromuscular junction were studied. Carbamaz
epine within a concentration range of 0.1-0.5 mmol/L reduced the peak
height of the action potential of the NG108-15 cells, whereas the memb
rane potential and membrane resistance were unaffected. Voltage clamp
revealed that the decrease in the action potential was due to the bloc
kage of the Na+, delayed K+ and transient Ca2+ currents. Carbamazepine
did not affect Ca2+-activated and A type K+ currents and long-lasting
Ca2+ current. In the frog neuromuscular junction, carbamazepine decre
ased the mean quantal content by a parallel shift in the frequency aug
mentation-potentiation (FAP) relation. It is concluded that carbamazep
ine blocks the voltage-dependent Naf, delayed Kf, and transient Ca2+ c
urrents and quantal transmitter release through a decrease of nerve ex
citation.