Pentobarbital: stereospecific actions of (+) and (-) isomers revealed on cultured mammalian neurons

See allHide authors and affiliations

Science  11 Jan 1980:
Vol. 207, Issue 4427, pp. 195-197
DOI: 10.1126/science.7350656


Stereoisomers of the barbiturate anesthetic pentobarbital were applied to mouse spinal neurons growing in tissue culture. Intracellular recordings of neuronal membrane properties revealed that the (+) and (-) isomers caused direct changes in membrane potential and conductance on some but not all of the cells tested. The action of the (+) isomer was predominantly excitatory, whereas the (-) isomer produced predominantly inhibitory responses. The (-) isomer was considerably more effective in potentiating inhibitory responses to the transmitter gamma-aminobutyric acid. The results show that pentobarbital has multiple effects on neuronal excitability and demonstrate the presence of stereospecific sites of barbiturate action on central neurons.