Kainic acid-induced lesion of rat retina: differential effect on cyclic GMP and benzodiazepine and GABA receptors.

Intraocular injection of kainic acid caused a marked decrease in GABA content in the rat retina and the almost complete loss of GAD activity in this tissue, within 3 days. Moreover, kainic acid produced a decrease of approximately 65% in the number of both [3H]diazepam and [3H]GABA binding sites without changing the apparent dissociation constants for their ligands. In contrast to that in brain areas, cyclic GMP content in the retina is neither influenced by kainic acid nor by the systemic administration of diazepam and muscimol.