INHIBITION OF GABA_A RECEPTOR-MEDIATED CURRENT RESPONSES BY ENOXACIN (NEW QUINOLONE) AND FELBINAC (NON-STEROIDAL ANTI-INFLAMMATORY DRUG) IN XENOPUS OOCYTES INJECTED WITH MOUSE-BRAIN MESSENGER RNA

Abstract

The convulsant interaction between enoxacin (ENX), a new quinolone antibacterial agent (NQ), and felbinac (FLB), a non-steroidal anti-inflammatory drug (NSAID), in vivo was reproduced as the change of GABA-induced current response in Xenopus oocytes injected with mouse brain mRNA. GABA (10 μM) response was inhibited by ENX in a dose-dependent manner, and IC₅₀ of ENX was 96 μM. Moreover, the inhibitory effect of ENX was 80-fold potentiated in the presence of 10 μM FLB. The GABA_A-antagonistic interaction between these two drugs in vitro was considered a possible mechanism of convulsant reaction after concomitant administration of NQs and NSAIDs in vivo.