The release of Leu5-enkephalin-like immunoreactivity from chicken retina is reduced by light in vitro.
A superfusion system was established to examine the efflux of endogenous Leu5-enkephalin-like immunoreactivity (LE-LI) from isolated chicken retinas. Superfusion with buffer containing high concentration of K+ (60 mM KCl) increased the efflux of LE-LI by 96%. This effect was not observed when Co2+ (4 mM CoCl2) was present. Exposing the retinas to light decreased the efflux of LE-LI by 59% compared to that observed during superfusion in the dark. No effect of ambient light could be detected in the presence of Co2+. Upon reverse-phase high-performance liquid chromatography the material released by the retina comigrated with synthetic Leu5-enkephalin. These results demonstrate that the release of LE-LI from retinal neurons is increased during the dark, and it is concluded that the lighting conditions exert their effects by modifying the state of polarization of the LE-LI amacrine cells and hence the release of LE-LI from these neurons.
Boelen
M K
MK
Department of Biology, University of Wollongong, N.S.W., Australia.
Dowton
M
M
Chubb
I W
IW
D000818:Animals; D002645:Chickens; D003035:Cobalt / Q000494:pharmacology; D004743:Enkephalin, Leucine / Q000378:metabolism*; D066298:In Vitro Techniques; D010775:Photic Stimulation; D011188:Potassium / Q000494:pharmacology; D011863:Radioimmunoassay; D012160:Retina / Q000378:metabolism* / Q000502:physiology
D003035:Cobalt; D004743:Enkephalin, Leucine; D011188:Potassium