Dowling J E, Ripps H
J Gen Physiol. 1977 Jan;69(1):57-74. doi: 10.1085/jgp.69.1.57.
The proximal negative response (PNR), a complex extracellular potential derived mainly from amacrine cell activity, was studied in the all-rod retina of the skate. Tetrodotoxin (10(-6) mg/ml) did not affect either the waveform or the latency of the response, indicating that the PNR reflects the graded, nonregenerative components of the amacrine cell potential. As regards its adaptive properties, the PNR exhibited both the extreme sensitivity to weak background light and the slow time course of light and dark adaptation that are characteristic of other responses from the proximal retina. Thus, the PNR, like the b-wave and ganglion cell discharge, appears to reflect adaptive processes located within the neural network of the inner retina.
近端负反应(PNR)是一种主要源自无长突细胞活动的复杂细胞外电位,在鳐鱼的全视杆视网膜中进行了研究。河豚毒素(10(-6)毫克/毫升)对反应的波形或潜伏期均无影响,这表明PNR反映了无长突细胞电位的分级、非再生成分。就其适应性特性而言,PNR既表现出对弱背景光的极高敏感性,又具有近端视网膜其他反应所特有的缓慢的明适应和暗适应时间进程。因此,PNR与b波和神经节细胞放电一样,似乎反映了位于视网膜内层神经网络内的适应性过程。