Carbamazepine facilitates effects of GABA on rat hippocampus slices.
Abstract
AIM: To study the influence of carbamazepine (Car) on GABA effect in hippocampus.
METHODS: Evoked potentials were recorded on pyramidal cells in CA1 after
stimulation (0.5 Hz, 50 microseconds) to Schaffer collaterals in rat hippocampal
slices (350 microns).
RESULTS: Car 0.1 and 0.2 mmol.L-1 did not affect field potentials, whereas Car
0.2 mmol.L-1 plus GABA (0.1-1 mmol.L-1) gave rise to a stronger inhibition on
field potentials than that of GABA alone. Bicuculline did not reverse Car
facilitation on GABA inhibition on field potentials. (-)-Baclofen was more
effective in inhibiting field potentials than GABA. Car 0.2 mmol.L-1 plus
(-)-baclofen (1-5 mumol.L-1) brought an inhibition stronger than that of
(-)-baclofen alone.
CONCLUSION: Car facilitates the effects of GABA on pyramidal cells in hippocampal
CA1 region, probably related to GABAB receptors.
Keywords:
METHODS: Evoked potentials were recorded on pyramidal cells in CA1 after
stimulation (0.5 Hz, 50 microseconds) to Schaffer collaterals in rat hippocampal
slices (350 microns).
RESULTS: Car 0.1 and 0.2 mmol.L-1 did not affect field potentials, whereas Car
0.2 mmol.L-1 plus GABA (0.1-1 mmol.L-1) gave rise to a stronger inhibition on
field potentials than that of GABA alone. Bicuculline did not reverse Car
facilitation on GABA inhibition on field potentials. (-)-Baclofen was more
effective in inhibiting field potentials than GABA. Car 0.2 mmol.L-1 plus
(-)-baclofen (1-5 mumol.L-1) brought an inhibition stronger than that of
(-)-baclofen alone.
CONCLUSION: Car facilitates the effects of GABA on pyramidal cells in hippocampal
CA1 region, probably related to GABAB receptors.