神经递质对暗视阈值反应的作用研究  

Effects of Aspartate、GABA、 Glycine and Dopamine on the Scotopic Threshold Response of the Cat ERG

作　　者：范先群[1] 张芸芸[1] 李海生[1] 奚渭清[1] 王仁 

机构地区：[1]上海第二医科大学附属第九人民医院眼科,200011

出　　处：《上海第二医科大学学报》1999年第1期12-15,共4页Acta Universitatis Medicinalis Secondae Shanghai

基　　金：卫生部青年科学研究基金!131932Y-2

摘　　要：目的探讨暗视阈值反应（scotopicthresholdresponse，STR）的细胞起源。方法应用玻璃体内注入神经活性物质，记录30只猫暗适应状态下的系列光视网膜电图（electroretinogram，ERG）。结果STR是暗适应状态下，很弱刺激光强记录到的负相波。天冬氨酸能将a波从ERG中分离出来，而STR和ERG的其他成分被完全抑制。GABA和甘氨酸选择性抑制STR，多巴胺对STR有明显抑制作用。结论STR的细胞起源和光感受器无关。无长突细胞对STR的产生有极其重要的作用。Objective To study the origin of the scotopic threshold response (STR) of cat electroretinogram (ERG). Methods CornealERG were recorded from 30 anesthetized cats under scotopic conditions. Aspartate. GABA. glycine and dopamine were given by intravitreal injection to suppress transmission from photoreceptors to second-and third-order neurons to identify the origin of the ERG. Results The STR was a long latency and small amplitude negative potential to very dim stimuli in the fully dark adapted retina. Intravitreal aspartate could dissociate a-wave from the ERG components and eliminate other ERG components (including the STR). GABA and glycine selectively suppressed the STR, Dopamine heavily suppressed the STR. ConclusionThere is no effect of photoreceptors on the origin of the STR, the STR may originate rod-driven depolarizing amacrine cells.

关 键 词：视网膜电图 暗适应 神经递质 暗视阈值反应 

分 类 号：R338.3[医药卫生—人体生理学]