Hyperpolarization-activated current (I(h)) in ganglion-cell photoreceptors.

ABSTRACT: Intrinsically photosensitive retinal ganglion cells (ipRGCs) express the photopigment melanopsin and serve as the primary retinal drivers of non-image-forming visual functions such as circadian photoentrainment, the pupillary light reflex, and suppression of melatonin production in the pineal. Past electrophysiological studies of these cells have focused on their intrinsic photosensitivity and synaptic inputs. Much less is known about their voltage-gated channels and how these might shape their output to non-image-forming visual centers. Here, we show that rat ipRGCs retrolabeled from the suprachiasmatic nucleus (SCN) express a hyperpolarization-activated inwardly-rectifying current (I(h)). This current is blocked by the known I(h) blockers ZD7288 and extracellular cesium. As in other syst

SUBMITTER: Van Hook MJ 

PROVIDER: S-EPMC3004865 | biostudies-literature | 2010 Dec

REPOSITORIES: biostudies-literature