Electrophysiology, GABA receptors

GABA receptors have been identified electrophysiologically and pharmacologically in all regions of the brain 293... 

W. Hevers, H. Luddens (1998). The diversity of GABA receptors pharmacological and electrophysiological properties of GABA channel subtypes. Mol. Neurobiol. 18 35. 

In the CNS of the cockroach Periplaneta americana, we have demonstrated the presence of GABA receptor-activated chloride ion channels Both the radiolabelled ligand binding and the electrophysiological studies have shown that the pharmacology of these insect CNS GABA receptors differs from that of the GABA receptors... 

Some years ago, Nielson (26) carried out a survey of the benzodiazepine binding sites in the neural tissue of some vertebrates and invertebrates, including locusts, and the results suggested that benzodiazepine receptors do not occur in the invertebrates but arose with the evolution of the bony fishes. Binding studies (22-24) together with our electrophysiological data indicate the presence of benzodiazepine receptors functionally associated with at least some insect central GABA receptors. 

The avermectins have been shown to increase chloride conductance in invertebrate electrophysiological preparations (J, JA,25) and modulate the binding of several GABA receptor-ionophore ligands (9, 10), but the molecular mechanisms underlying their neurotoxicity remain poorly defined. Recently, Abalis e t al. (1 ) reported an avermectin Independent stimulation of chloride uptake in rat brain vesicles tnat... 

Studying GABA receptor-mediated Cl flux using an incubation time of 5 s, a rapid decrease in the measurement of ion fluxes in the synaptoneurosome preparation would be expected as a result of desensitization of the GABA receptor and of equilibration of across the membrane. Electrophysiological measure-... 

Electrophysiological evidence indicates that spinosyns can alter nicotinic currents in neuronal cell bodies from CNS of the American cockroach [P. americana (L)j. The effect is correlated with toxicity to neonate Heliothis virescens larvae. It can be su ested that the spinosyns affect nAChR and GABA receptors through a so-called undetermined mecdianism and differ from that of neonicotinoids... 

Enna S J and Gallagher J P. (1983) Biochemical and electrophysiolog-ical characteristics of mammalian GABA receptors Int Rev. Neurobiol 24,181-212... 

Electrophysiological data suggest that there are two GABA-recognition sites per GABAA-receptor complex [ 13]. An increase in the concentration of GABA results in an... 

Orexins increase transmitter release. This has been shown in electrophysiolog-ical studies for acetylcholine release in the myenteric plexus of the ileum and for GABA and glutamate release in a series of locations of the central nervous system (Table 5) in other words, presynaptic orexin receptors serve as heteroreceptors. Experiments on human tissue are so far lacking. In some of the experimental models listed in Table 5 orexin-A and orexin-B were studied and orexin-B was at least as... 

Electrophysiological studies show that benzodiazepines, barbiturates and sodium valproate facilitate GABAergic transmission in the animal brain. Further evidence comes from studies on the GABA-benzodiazepine receptor complex, the order of potency of a series of benzodiazepines to displace [3H] diazepam from its receptor site being clearly correlated with the antagonism of pentylenetetrazol seizures, but not with electroconvulsive seizures. However, most classes of anticonvulsants appear to facilitate... 

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