Starburst amacrine cells change from spiking to nonspiking neurons during retinal development.
The membrane excitability of cholinergic (starburst) amacrine cells was studied in the rabbit retina during postnatal development. Whole-cell patch-clamp recordings were made from 110 displaced starburst cells in a thin retina] slice preparation of rabbits between postnatal days P1 and P56 old. We report that displaced starburst cells undergo a dramatic transition from spiking to nonspiking, caused by a loss of voltage-gated Na currents. This change in membrane excitability occurred just after eye opening (P10), such that all of the starburst cells tested before eye opening had conspicuous tetrodotoxin-sensitive Na currents and action potentials, but none tested after the first 3 postnatal weeks had detectable Na currents or spikes. Our results suggest that starburst cells use action potentials transiently during development and probably play a functional role in visual development. These cells then cease to spike as the retina matures, presumably consistent with their role in visual processing in the mature retina.
Zhou
Z J
ZJ
Department of Physiological Science, University of California, Los Angeles 90024-1527, USA.
Fain
G L
GL
D000200:Action Potentials / Q000187:drug effects; D000375:Aging / Q000502:physiology*; D000818:Animals; D000831:Animals, Newborn; D066298:In Vitro Techniques; D007700:Kinetics; D018408:Patch-Clamp Techniques; D011817:Rabbits; D012160:Retina / Q000166:cytology* / Q000254:growth & development / Q000502:physiology*; D012165:Retinal Ganglion Cells / Q000166:cytology / Q000502:physiology*; D013779:Tetrodotoxin / Q000494:pharmacology; D013997:Time Factors
D013779:Tetrodotoxin