Factors That Affect the Binding and Uptake of Gaba by Brain Tissue1

As previously reported, when brain tissue was homogenized in isotonic solution and the suspension was centrifuged, less GABA was found in the sediment if the solution contained only sucrose than if it contained some NaCl. NaBr and Nal were as effective as the chloride. Less effective were Na2SOi, Na‐phosphate, and the chlorides of K, Li, choline, NHt, Ca or Mg. Ouabain and protoveratrine inhibited the extra binding promoted by NaCl in brain suspensions and inhibited the uptake of GABA by respiring slices of cerebral cortex; tetrodotoxin alone had no effect in either case but reversed the effect of protoveratrine. Considerable inhibition of the uptake of GABA by brain slices was observed with glutamic acid, imipramine, chlorpromazine, procaine, xylocaine or picrotoxin but not with acetylcholine, prostigmine, norepinephine, dopamine, chloral hydrate, chloretone, pentylentetrazol or methionine sulphoximine.