SP-8-CPT-cAMP对神经节细胞和无长突细胞间示踪剂藕连的影响

The Effect of SP-8-CPT-cAMP on the Tracer Coupling between the Retinal Ganglion Cells and Amacrine Cells

目的:研究SP-8-CPT-cAMP对兔眼视网膜神经节细胞和无长突细胞间示踪剂藕连的影响。方法:兔眼视网膜组织培养,并用SP-8-CPT-cAMP(环腺苷酸的类似物)处理。采用细胞显微注射方法将神经生物素注射入视网膜组织单个活体关闭性α亚型(OFF-α)神经节细胞中,终止注射后,用4%甲醛固定,1:600 Cy3-链亲合素反应,并用共焦显微镜测定在藕连的神经节细胞和无长突细胞中通过缝隙连接扩散的示踪剂的量。结果:在被注射的神经节细胞(GO)树突区及树突区之外可见未注射的神经节细胞(G1)被染色,此外还可见数十个胞体较小、位于内核层的明亮的(A1)和暗的(A2)无长突细胞被染色。经SP-8-CPT-cAMP处理后,藕连的G1,A1,A2的神经生物素示踪剂浓度明显高于未用药组(注射后1h)。结论:OFF-α神经节细胞和无长突细胞间存在缝隙连接,神经节细胞间也存在直接缝隙连接。SP-8-CPT-cAMP增加了神经节细胞藕连网缝隙连接的通透性。眼科学报:2003 ;19:126-129。

Purpose:To study the effect of SP-8-CPT-eAMP on the tracer coupling between the retinal ganglion cells and amaerine cells in rabbits. Methods :The retinas of rabbit were cultured and treated with SP-8-CPT-cAMP .4% neurobiotin was injected into retinal single OFF-α ganglion cell with micro-injection, following tissue fixation with 4%paraformaldehyde, Cells were visualized with 1:600 streptavidin-CyS.The intensity of tracer diffusing through the gap junctions among the ganglion cells and amaerine cells was calculated with confocal microscope. Results:In the dendritic field of injected ganglion cells and cross the field some other ganglion cells(G1) and amaerine cells locating in the inner nuclear layer were stained. Two types of amaerine cells: brighter one (A1) and dimmer one (A2) were found.The intensity of neurobiotin in coupled G1,A1,A2 after treated with SP-8-CPT-cAMP is much higher than that of the untreated retinas . Conclusion:The gap junctions exist among the OFF-α ganglion cells and between OFF-a ganglion cells and amaerine cells. SP-8-CPT-cAMP increases the permeability of gap junction in OFF-α ganglion cell network. Eye Science 2003 ; 19 : 126-129.