A physiologically active kainic acid-preferring receptor in chicken retina

Neurotoxicity induced by intravitreal injections of kainic acid in the chicken retina was effectively antagonized by piperidine 2,3-dicarboxylic acid and to a lesser extent D-gamma-glutamylglycine. 2-Amino-5-phosphonovaleric acid and glutamic acid diethyl ester were much less effective antagonists. These effects probably result from interactions with a kainic acid-preferring receptor localized on the OFF-centre bipolar cells. Piperidine 2,3-dicarboxylic acid and D-gamma-glutamylglycine also blocked selectively the OFF-responses of ganglion cells while glutamic acid diethyl ester was without effect. 2-Amino-5-phosphonovaleric acid rapidly blocked ON and, much more slowly, OFF-responses. These results are consistent with a role for kainic acid-preferring receptors located on the OFF-centre bipolar cells in chicken retina in physiological transmission between photoreceptors and the OFF-centre bipolar cells.