Neurotransmitter uptake into slices of rat cerebral cortex in vitro: effect of slice size.

Abstract

Abstract— The uptake of [14C]GABA, [14C]taurine, [3H]β‐alanine and [14C]dopamine was compared in slices of rat cerebral cortex of three different sizes (0.1 × 0.1 × 2 mm, 0.2 × 0.2 × 2 mm and 0.4 × 0.4 × 2 mm prepared with a mechanical tissue chopper). [14C]Taurine and [3H]β‐alanine uptake increased whereas [14C]GABA uptake decreased with increasing slice size. [14C]Dopamine uptake was optimal in 0.2 × 0.2 × 2 mm slices. Increasing slice size was shown to decrease inhibition of [3H]β‐alanine and [14C]GABA uptake by l‐2,4‐diaminobutyric acid. Lactate dehydrogenase activity increased with increasing slice size indicating decreased tissue damage or increased cellular integrity. The possibility that varying slice size can be used to distinguish between neuronal and glial uptake is discussed. It is suggested that taurine uptake in the cerebral cortex is predominantly glial.