LOCALIZATION OF SENSITIVE SITES TO TAURINE, γ-AMINOBUTYRIC ACID, GLYCINE AND β-ALANINE IN THE MOLECULAR LAYER OF GUINEA-PIG CEREBELLAR SLICES

Abstract

1 The localization, in the molecular layer of guinea-pig cerebellar slices, of the sites most sensitive to iontophoretically applied taurine, γ-aminobutyric acid (GABA), glycine and β-alanine was investigated. 2 The most sensitive sites were located (expressed as the distance from the Purkinje cell body to the pial surface): 0 μm, 60 μm and 220 μm for taurine; 0 μm and 180 μm for GABA; 80 μm and 200 μm for glycine, and 80 μm, 180 μm and 300 μm for β-alanine. 3 The sensitive site (at 0 μm) to GABA was considered to represent the basket synapses on the Purkinje cell soma, while the sites (60 to 80 μm and 200 to 300 μm) for taurine, glycine and β-alanine were tentatively assigned to the synapses of the stellate neurones on the Purkinje cell dendrites. 4 Inhibitory actions of all four amino acids tested at the most sensitive sites were antagonized by both picrotoxin and strychnine. 5 The possibility that taurine might be the neurotransmitter of the stellate neurones in guinea-pig cerebellum is discussed.