Benzodiazepines and the mammalian retina. III. Postnatal development

Iontophoretic effects of the benzodiazepine receptor agonist, flurazepam, and antagonist, flumazepil (RO-15-1788) on the retinal ganglion cells of kittens (7-9 weeks of age) have been compared with those of adult cats (18-22 weeks of age). In the adult retina, flurazepam decreased and flumazepil increased the visually evoked and spontaneous firing of ON-, but produced no effects on the response of OFF-retinal ganglion cells. However, in the kittens retina, in which ON-cells' selectivity to GABA is not fully developed, both the visually evoked and spontaneous activities of ON- and OFF-cells were inhibited by flurazepam and enhanced by flumazepil. This suggests that postnatal development of benzodiazepine action parallels that of GABA action at the retinal ganglion cells in the cat retina.