TY - JOUR
T1 - Light-dependent regulation of dopamine receptors in mammalian retina
AU - Dubocovich, Margarita L.
AU - Lucas, Rita C.
AU - Takahashi, Joseph S.
N1 - Funding Information:
This investigation was supported by USPHS Grant EY 04788 to M.L.D. and Searle Leadership Fund for the Life Sciences and Alfred P. Sloan Research Fellowship BR-2366 to J.S.T. We are grateful to Dr. R. Virus for performing the analysis of variance. We thank Maureen Gremillion for technical assistance and Veronica L. Lawson for typing the manuscript.
PY - 1985/6/3
Y1 - 1985/6/3
N2 - The specific binding of [3H]spiperone, a D-2 dopamine receptor ligand, in retinas from rabbits kept one week in constant light was significantly lower than in retinas from rabbits exposed to constant dark. Constant light did not alter the binding of [3H]spiperone in the striatum, where melatonin does not inhibit dopamine release. The decrease in [3H]spiperone binding induced by constant light in retina appears to be associated with the activation of inhibitory melatonin receptors on dopaminergic neurons. In support of this hypothesis, treatments that elevate melatonin concentrations, such as dark or melatonin administration, reversed the light-induced down-regulation of D-2 dopamine binding sites in retina. It is concluded that the decrease in melatonin levels in constant light disinhibits the dopamine-containing retinal neurons in vivo leading to elevated dopamine release and subsequent D-2 dopamine receptor down-regulation.
AB - The specific binding of [3H]spiperone, a D-2 dopamine receptor ligand, in retinas from rabbits kept one week in constant light was significantly lower than in retinas from rabbits exposed to constant dark. Constant light did not alter the binding of [3H]spiperone in the striatum, where melatonin does not inhibit dopamine release. The decrease in [3H]spiperone binding induced by constant light in retina appears to be associated with the activation of inhibitory melatonin receptors on dopaminergic neurons. In support of this hypothesis, treatments that elevate melatonin concentrations, such as dark or melatonin administration, reversed the light-induced down-regulation of D-2 dopamine binding sites in retina. It is concluded that the decrease in melatonin levels in constant light disinhibits the dopamine-containing retinal neurons in vivo leading to elevated dopamine release and subsequent D-2 dopamine receptor down-regulation.
KW - D-2 dopamine receptor down-regulation
KW - [H]spiperone binding
KW - melatonin levels
KW - rabbit retina and striatum
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U2 - 10.1016/0006-8993(85)90485-8
DO - 10.1016/0006-8993(85)90485-8
M3 - Article
C2 - 2988696
AN - SCOPUS:0021814556
SN - 0006-8993
VL - 335
SP - 321
EP - 325
JO - Brain Research
JF - Brain Research
IS - 2
ER -