GABABReceptor Antagonism: Facilitatory Effects on Memory Parallel Those on LTP Induced by TBS but Not HFS

摘要: The present experiments used CGP 35348, a selective GABAB receptor antagonist with significantly higher affinity for post- versus presynaptic receptors, to dissociate the role of concentration stimulation mode in determining whether blockade facilitates or suppresses long-term potentiation (LTP). was applied by pressure ejection one two recording sites area CA1 hippocampal slices before LTP induced at both either theta burst high-frequency (TBS HFS). TBS produced dose-dependent facilitation that turned into depression highest tested, result reflecting balance between drug’s postsynaptic disinhibitory effect and its action on autoreceptors regulating release GABA. In contrast, HFS-induced increased monotonically drug concentration, suggesting receptors is only factor contributing LTP. To test relevance sets results, we performed behavioral studies examining different dosages spatial retention found memory enhanced intermediate but not very low high concentrations, reminiscent bell-shaped dose–response curve obtained TBS-induced These findings are consistent notion electrical modeled after endogenous theta-modulated activity patterns bears more behavior than does arbitrary tetanic trains.