[Inhibition of transducin by lithium: electrophysiological demonstration using the isolated retina].
Recently Avissar et al. have established that Li+ can inhibit G proteins implicated in brain function. In order to investigate the effect of Li+ on transducin, the evolution of the electroretinogram (ERG) recorded on isolated rat retina has been studied in presence of lithium. Results indicate that 10(-5) M Li+ had no effect on ERG while 10(-3) M Li+, which corresponds to therapeutic blood levels, significantly decreases ERG amplitude. This effect being nearly totally inhibited by cholera toxin (75 micrograms/l), it is concluded that Li+ acts on transducin and so inhibits the visual transduction process.
Meyniel
G
G
Laboratoire de Biophysique, I.N.S.E.R.M. U. n. 71, Facultés de Médecine et de Pharmacie, Clermont-Ferrand.
Doly
M
M
Gaillard
G
G
D000818:Animals; D002772:Cholera Toxin / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004596:Electroretinography; D008094:Lithium / Q000494:pharmacology*; D051381:Rats; D012160:Retina / Q000502:physiology*; D015293:Transducin / Q000037:antagonists & inhibitors*
D002772:Cholera Toxin; D008094:Lithium; D015293:Transducin
Inhibition de la transducine par le lithium: mise en évidence électrophysiologique sur rétine isolée.