Intrinsic ON Responses of the Retinal OFF Pathway Are Suppressed by the ON Pathway

• DOI: 10.1523/jneurosci.1718-06.2006
• Publication Date: 2006-11-16T02:56:35Z
• Authors: René C. Rentería; Ning Tian; Jianhua Cang; Shigetada Nakanishi; Michael P. Stryker; David R. Copenhagen
• Keywords: Male; Mice, Knockout; Neurons; Retinal Ganglion Cells; 0301 basic medicine; Retinal Bipolar Cells; Action Potentials; Glutamic Acid; Neural Inhibition; Receptors, Metabotropic Glutamate; Synaptic Transmission; Retina; Mice, Inbred C57BL; Mice; 03 medical and health sciences; Excitatory Amino Acid Agonists; Reaction Time; Animals; Female; Visual Pathways; Excitatory Amino Acid Antagonists; Visual Cortex

Parallel ON and OFF pathways conduct visual signals from bipolar cells in the retina to higher centers brain. responses are thought originate by exclusive use of metabotropic glutamate receptor 6 (mGluR6) expressed retinal cells. Paradoxically, we find ganglion mGluR6-null mice, but they occur at long latency. The long-latency not blocked or cholinergic antagonists produced activation receptive field surrounds. We show that these longer-latency initiated pathways. Our results expose a previously unrecognized intrinsic property generates light onset. In observed cortex, indicating can be conducted reliably areas. wild-type (WT) APB ( dl -2-amino-4-phosphonobutyric acid), an mGluR6 agonist, blocks normal, short-latency unmasks ones. potentially confusing pathway actively suppressed WT mice via two pharmacologically separable circuits activated system retina. Consequently, propose major function signaling is suppression mistimed, therefore inappropriate, light-evoked responses.