CGP 55845A: a potent antagonist of GABAB receptors in the CA1 region of rat hippocampus.
The new GABAB receptor antagonist CGP 55845A was tested on pre- and post-synaptic GABAB receptors in the hippocampus. CGP 55845A (1 microM) blocked (-)-baclofen (5-10 microM)-induced postsynaptic hyperpolarization and depression of evoked IPSPs and EPSPs. It also blocked three physiological consequences of GABAB receptor activation: the late IPSP, paired-pulse depression of IPSCs, and heterosynaptic depression of EPSPs. Therefore, CGP 55845A is an antagonist at pre- and post-synaptic GABAB receptors in the hippocampus and is approximately three orders of magnitude more potent than previously described GABAB receptor antagonists.
Davies
C H
CH
Department of Pharmacology, Medical School, University of Birmingham, Edgbaston, U.K.
Pozza
M F
MF
Collingridge
G L
GL
D000818:Animals; D001418:Baclofen / Q000037:antagonists & inhibitors / Q000494:pharmacology; D005071:Evoked Potentials / Q000187:drug effects; D058788:GABA-B Receptor Antagonists; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism*; D066298:In Vitro Techniques; D010721:Phosphinic Acids / Q000494:pharmacology*; D011412:Propanolamines / Q000494:pharmacology*; D051381:Rats; D018080:Receptors, GABA-B; D013569:Synapses / Q000187:drug effects / Q000378:metabolism; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
D058788:GABA-B Receptor Antagonists; D010721:Phosphinic Acids; D011412:Propanolamines; D018080:Receptors, GABA-B; C085075:CGP 55845A; D005680:gamma-Aminobutyric Acid; D001418:Baclofen