STRYCHNINE-SENSITIVE GLYCINE RECEPTORS IN CULTURED PRIMARY NEURONS FROM RAT NEOCORTEX

After 1 day in vitro (DIV) glycine (1 mM) evoked chloride-dependent me mbrane currents in about 50% of primary cultured rat neocortical neuro ns and more than 98% of the cells were glycine-sensitive after 2 DIV l asting for at least up to 12 DIV which was similar to GABA chemosensit ivity. Strychnine (IC50 40 nM) and picrotoxin (30 muM) but not bicucul line (50 muM) blocked the glycine-evoked currents. The results provide evidence for a very early expression of glycine receptors on cortical neurons leading to a powerful chloride channel-operating capacity dur ing early development.