Glycine potentiates the NMDA-induced release of dopamine through a strychnine-insensitive site in the rat striatum.

A new procedure, involving a push-pull cannula, was used to estimate the release of [3H]dopamine ([3H]DA) synthesized from [3H]tyrosine in rat striatal slices. NMDA (5 x 10(-5) M) stimulated [3H]DA release in the absence of Mg2+, and this effect was abolished in the presence of Mg2+ (10(-3) M), MK-801 (10(-6) M) or kynurenate (10(-4) M). Glycine markedly potentiated the NMDA-evoked response and reversed the inhibitory effect of kynurenate in the absence of Mg2+ and in the presence of strychnine (10(-6) M).