Wan W, Geiger J D
Department of Pharmacology and Therapeutics, University of Manitoba, Faculty of Medicine, Winnipeg, Canada.
Neurosci Lett. 1990 Sep 4;117(1-2):160-4. doi: 10.1016/0304-3940(90)90137-x.
Adenosine receptors of A1 and A2 subtypes on retino-collicular projections in rat were studied using [3H]cyclohexyladenosine ([3H]CHA), [3H]N-ethylcarboxamidoadenosine ([3H]NECA), and [3H]CGS 21680. Unilateral enucleation significantly reduced by 51% [3H]CHA binding to A1 sites, and by 42% the A1 component of [3H]NECA binding in contralateral SC. The binding of [3H]CGS 21680 and [3H]NECA to A2 sites was not significantly affected by enucleation procedures. No significant reductions in adenosine receptor binding were observed in SC from rats exposed to a dark environment for three weeks. The reductions in A1 but not A2 adenosine receptor binding strongly suggests that A1 sites are presynaptically located on retinal projections and are vulnerable to deafferentiation-, but not visual deprivation-induced decreases.
使用[3H]环己基腺苷（[3H]CHA）、[3H]N-乙基羧基酰胺腺苷（[3H]NECA）和[3H]CGS 21680研究了大鼠视网膜-视顶盖投射上A1和A2亚型的腺苷受体。单侧眼球摘除术使对侧上丘中[3H]CHA与A1位点的结合显著减少51%，[3H]NECA结合的A1成分减少42%。[3H]CGS 21680和[3H]NECA与A2位点的结合不受眼球摘除术的显著影响。在黑暗环境中暴露三周的大鼠的上丘中，未观察到腺苷受体结合有显著减少。A1而非A2腺苷受体结合的减少强烈表明，A1位点位于视网膜投射的突触前，易受去传入作用影响，但不受视觉剥夺诱导的减少影响。
