Abstract
Studies of the Na+‐dependent and Na+‐independent binding of [3H] γ‐aminobutyric acid ([3H]GABA) and [3H]muscimol to central nervous system (CNS) subcellular preparations have been briefly reviewed and analyzed. Although some of the binding processes that have been detected in vitro, in the presence or absence of Na+, appear to represent GABA‐receptor interactions, further studies conducted with physiologic media and with highly purified membrane preparations are necessary in order to define the properties of those neuronal membrane receptors that mediate the in vivo actions of GABA.