Intravitreal kainic acid permanently eliminates off-pathways from chicken retina

Kainic acid rapidly suppresses both ON- and OFF-visually evoked responses in the tectum after injection into the vitreous of chicken eyes. One week after injection the OFF-responses were still suppressed, while ON-responses were detected of similar magnitude but of simplified form to those of control eyes. It is suggested that kainic acid selectively destroys OFF- rather than ON-bipolar cells, while the simplification of the ON-responses is due to the destruction of amacrine cells.