The effects of pentobarbital and related compounds on frog motoneurons

@article{Nicoll1980TheEO,
  title={The effects of pentobarbital and related compounds on frog motoneurons},
  author={Roger A Nicoll and J. Martin Wojtowicz},
  journal={Brain Research},
  year={1980},
  volume={191},
  pages={225-237}
}
The effect of pentobarbital (PB) and related compounds on frog motoneurons was examined with sucrose gap recording from the ventral roots. PB was found to: (1) depress the action of glutamate, (2) selectively enhance the action of GABA, (3) reverse the non-competitive picrotoxin antagonism of GABA and the competitive strychnine antagonism of beta-alanine, but not the competitive bicuculline methiodide antagonism of GABA, and (4) elicit a GABAmimetic hyperpolarization. The first three actions… Expand
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DISTINCTION BETWEEN THE EFFECTS OF BARBITURATES, BENZODIAZEPINES AND PHENYTOIN ON RESPONSES TO γ‐AMINOBUTYRIC ACID RECEPTOR ACTIVATION AND ANTAGONISM BY BICUCULLINE AND PICROTOXIN
  • M. Simmonds
  • Chemistry, Medicine
  • British journal of pharmacology
  • 1981
TLDR
The spectrum of drug activity in reducing the potency of picrotoxin correlates well with the reported anticonvulsant effects of these drugs against kindled amygdaloid seizures. Expand
Pentobarbital depressant effects are independent of GABA receptors in auditory thalamic neurons.
TLDR
In summary, the pentobarbital acted at low concentrations to depress thalamocortical neurons and reduced Na(+)-dependent rectification on depolarization and lowered the slope resistance over a wide voltage range. Expand
Direct activation of GABAA receptors by barbiturates in cultured rat hippocampal neurons.
TLDR
It is concluded that the gating of the GABAA receptor channel by PHB and PB is functionally similar to that produced by the natural agonist GABA alone, but distinct from that obtained when barbiturates modulate the response to GABA. Expand
Are the toxicities of pentobarbital and ethanol mediated by the GABA-benzodiazepine receptor-chloride ionophore complex?
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It was found that isopropylbicyclophosphate (IPPO), a cage convulsant which binds at or near the chloride ionophore, greatly reduces the overall mortality and increases latency to death of animals pretreated with a lethal dose of pentobarbital, and IPPO significantly reduced the duration of loss of righting reflex induced by ethanol. Expand
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