Benzodiazepine receptor ligand actions on GABA responses. Benzodiazepines, CL 218872, zopiclone.

@article{Skerritt1984BenzodiazepineRL,
  title={Benzodiazepine receptor ligand actions on GABA responses. Benzodiazepines, CL 218872, zopiclone.},
  author={John H. Skerritt and Robert L. Macdonald},
  journal={European journal of pharmacology},
  year={1984},
  volume={101 1-2},
  pages={
          127-34
        }
}
The effects on GABA (4-aminobutyric acid) responses of several benzodiazepine and nonbenzodiazepine benzodiazepine receptor ligands were examined using mouse spinal cord neurons in dissociated cell culture. Diazepam, clonazepam and nitrazepam enhanced GABA responses potently at low nanomolar concentrations. Diazepam and clonazepam were most potent with significant enhancement at 1 nM and peak enhancement of 80.7 and 50.2% at 10 nM respectively. Nitrazepam was least potent with no significant… Expand
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The results with beta-carbolines are consistent with their behavioural profile in vivo and with neurochemical studies of their effects upon GABA-benzodiazepine receptor complexes, and certain purines are also able to interact with these complexes. Expand
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The main properties of a representative of this novel class of specific benzodiazepine antagonists are described, whose unique pharmacological activity is to prevent or abolish in a highly selective manner at the receptor level all the characteristic centrally mediated effects of active Benzodiazepines. Expand
Benzodiazepines specifically modulate GABA-mediated postsynaptic inhibition in cultured mammalian neurones
TLDR
The effect of DZ and CDZ on amino acid-mediated postsynaptic responses in cultured mammalian spinal cord neurones is studied and it is reported that the BDZ selectively modify GABA-mediatedPostsynaptic inhibition in a dose-dependent fashion, augmenting the response at low doses and antagonising the response in higher doses. Expand
Electrophysiological evidence that GABA potentiation in vivo correlates with benzodiazepine receptor affinity
Abstract Since the inhibition of cortical neurons evoked by electrical stimulation of the surface of the cerebral cortex is believed to be mediated by endogenous GABA, the effects of fiveExpand
gamma-Aminobutyric acid enhancement of CL 218,872 affinity and evidence of benzodiazepine receptor heterogeneity.
TLDR
The results of these studies show that GABA enhances the affinity of CL 218,872 for the central benzodiazepine receptor(s) and that the inhibition of [3H]flunitrazepam binding by CL 218-872 in bovine retina, rat cerebellum, and cerebral cortex may be explained by interactions with two classes of independent binding sites. Expand
Benzodiazepine binding and interactions with the GABA receptor complex in living cultures of rat cerebral cortex
TLDR
The efficacy of a number of benzodiazepines, xanthine derivatives and other drugs in competition experiments is similar to that seen in neuronal membrane preparations, and suggests that the Benzodiazepine binding site studied in these investigations is the same as that found in neuronal membranes preparations. Expand
CL 218872 antagonism of diazepam induced loss of righting reflex: evidence for partial agonistic activity at the benzodiazepine receptor.
TLDR
The ability of CL 218872 to antagonize diazepam induced loss of righting reflex and enhance the anticonvulsant effect of diazepAM in mice suggests that this triazolopyridazine may act as a partial agonist at the BZD receptor. Expand
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