Fries Julia E, Wheeler-Schilling Thomas H, Kohler Konrad, Guenther Elke
Experimental Ophthalmology, University Eye Hospital, Tübingen, Germany.
Brain Res Mol Brain Res. 2004 Nov 4;130(1-2):1-6. doi: 10.1016/j.molbrainres.2004.06.041.
P2Y receptors are metabotropic G-protein linked purinergic receptors, which are especially widespread in the central nervous system. The purpose of the present study was to determine the distribution patterns of P2Y receptors in distinct retinal cell types in the adult retina. Retinal ganglion cells (RGC), bipolar cells (BPC) and Muller cells (MC) of adult pigmented rats were analyzed for their expression of P2Y-receptor subtypes P2Y1, P2Y2, P2Y4, and P2Y6 by single-cell reverse transcription polymerase chain reaction (SC-RT-PCR). SC-RT-PCR resulted in a positive amplification signal for all P2Y-receptor subtype mRNAs in all cell types examined. However, subtype distribution differed among the different cell types. The percentage of cells expressing a distinct P2Y subtype was: (a) for RGCs: 80% with P2Y1, 100% with P2Y2, 30% with P2Y4 and 50% with P2Y6, (b) for BPCs: 60% with P2Y1, 40% with P2Y2, 20% with P2Y4 and 80% with P2Y6, and (c) for MCs: 60% with P2Y1, 80% with P2Y2, 60% with P2Y4 and 100% with P2Y6. Our data show that different subtypes of P2Y receptors (P2Y1, P2Y2, P2Y4 and P2Y6) are expressed in various retinal cells and indicate that extracellular purines and pyrimidines act on RGCs, BPCs and MCs via different P2Y receptors.
P2Y受体是与代谢型G蛋白偶联的嘌呤能受体，在中枢神经系统中分布尤为广泛。本研究的目的是确定成年视网膜中不同视网膜细胞类型中P2Y受体的分布模式。通过单细胞逆转录聚合酶链反应（SC-RT-PCR）分析成年色素沉着大鼠的视网膜神经节细胞（RGC）、双极细胞（BPC）和穆勒细胞（MC）中P2Y受体亚型P2Y1、P2Y2、P2Y4和P2Y6的表达情况。SC-RT-PCR在所有检测的细胞类型中均产生了所有P2Y受体亚型mRNA的阳性扩增信号。然而，不同细胞类型中的亚型分布有所不同。表达特定P2Y亚型的细胞百分比为：（a）RGC：P2Y1为80%，P2Y2为100%，P2Y4为30%，P2Y6为50%；（b）BPC：P2Y1为60%，P2Y2为40%，P2Y4为20%，P2Y6为80%；（c）MC：P2Y1为60%，P2Y2为80%，P2Y4为60%，P2Y6为100%。我们的数据表明，P2Y受体的不同亚型（P2Y1、P2Y2、P2Y4和P2Y6）在各种视网膜细胞中均有表达，这表明细胞外嘌呤和嘧啶通过不同的P2Y受体作用于RGC、BPC和MC。
