Glycine-evoked release of [3H]acetylcholine from rat striatal slices is independent of the NMDA receptor.

KCl-, NMDA-, and glycine-evoked release of [3H]acetylcholine was studied in superfused rat striatal slices. KCl-evoked release of [3H]acetylcholine was inhibited by 1.2 mM MgCl2 and 100 microM lidocaine. Similarly, NMDA-evoked release was inhibited by MgCl2 and lidocaine as well as 10 microM CGS 19755, a competitive antagonist at NMDA receptors, and 10 nM MK-801, a noncompetitive antagonist of NMDA-induced responses. Glycine-evoked release was calcium-dependent and was inhibited by 0.1 microM strychnine whereas KCl- and NMDA-evoked release were resistant to strychnine. In addition, lidocaine inhibited the glycine-induced response. Cross-tachyphylaxis was not observed between NMDA- and glycine-evoked release. These results indicate that the strychnine-sensitive, glycine-evoked release of [3H]acetylcholine is independent of the NMDA receptor.