Na+-independent L-aspartate binding sites in chick brain.

1. One binding component with aKd value of 200×10−9 M and half-life of the ligand binding component of 30 min was found. 2. Chloride ions produced a significant increase ofl-[3H]aspartate andl-[3H]glutamate binding. 3.l-Glutamate,l-ibotenate,l-quisqualate, anddl-homocysteic acid were potent inhibitors ofl-[3H]aspartate binding. 4. In all brain regions major increases of binding were observed during the third week of the in ovo period of life.