Reduction of endogenous level, uptake and release of taurine after intrastriatal kainic acid injection

Abstract

Rats received single unilateral stereotaxic injections of 2 μg of kainic acid into the left caudate nucleus 10 days before sacrifice. On the lesioned side, a significant reduction of endogenous taurine levels and high affinity uptake of 3H-taurine into crude synaptosomal (P 2) fractions to about 75% of control values was found. In agreement with previous reports on the neurotoxic action of kainic acid, a marked reduction of endogenous GABA levels and 14C-GABA uptake into P 2-fractions was observed, while 3H-dopamine uptake was not significantly changed. In superfusion experiments with prelabeled P 2-fractions prepared from lesioned striata, K +(56 mM)-induced release of 3H-taurine and 14C-GABA, but not of 3H-dopamine, was reduced. The results are compatible with the hypothesis that taurine in the striatum of the rat is partially localized in interneurones.