Control of retinal information coding by GABAB receptors
Control of retinal information coding by GABAB receptors
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GABAB 受体对视网膜信息编码的控制
作者：
Z. Pan;MM Slaughter
采用常规细胞内记录技术和药物应用，研究了虎蝾螈视网膜-眼杯中无突细胞和神经节细胞的定向选择性。巴氯芬是一种GABAB受体激动剂，可以增强一些定向选择性三阶神经元的正常定向反应。在大约30%正常情况下没有方向性的细胞中，巴氯芬诱导了方向选择反应。当使用2-氨基-4-磷酸丁酸酯（APB）分离OFF途径时，这种效果尤其明显。APB和巴氯芬对诱导定向细胞的影响的比较表明，on和OFF通道中的定向信息通常是分开处理的，并且经常不对齐。这往往会模糊从躯体观察到的方向性。微毒素的应用阻断了某些细胞正常的定向选择性和巴氯芬诱导的定向选择性。微型毒素和士的宁的混合几乎阻断了所有细胞的方向性。在正常方向和诱导方向上，零方向响应因细胞而异，在小的去极化，无电压响应或超极化之间。注入正电流通常显示“沉默”抑制。一些诱导的定向选择细胞在零方向上没有表现出任何抑制的迹象。对巴氯芬的相似反应，GABA和甘氨酸拮抗剂的影响，以及零方向反应的特征表明，正常和诱导的方向性来自相同的来源或机制。巴氯芬也诱导定向选择性，但很少观察到。
The directional selectivity of amacrine and ganglion cells was studied using conventional intracellular recording techniques and drug application in the superfused retina-eyecup preparation of the tiger salamander. Baclofen, a GABAB receptor agonist, enhanced normal directional responses in some directionally selective third-order neurons. In about 30% of the cells that were not normally directional, baclofen induced direction-selective responses. This effect was particularly marked when 2-amino-4-phosphonobutyrate (APB) was used to isolate the OFF pathway. Comparisons of the effects of APB and baclofen on induced directional cells indicate that directional information in the ON and OFF channels is often handled separately and frequently is not aligned. This tends to obscure the observation of directionality as seen from the soma. Application of picrotoxin blocked both normal directional selectivity and baclofen-induced directional selectivity in some cells. Superfusion of picrotoxin and strychnine together blocked directionality in almost all cells. In both normal and induced directionality, the null direction response varied from cell to cell between a small depolarization, no voltage response, or a hyperpolarization. Injection of positive current often revealed “silent” inhibition. Some induced direction-selective cells did not show any evidence of inhibition in the null direction. The similarities in the response to baclofen, the influence of GABA and glycine antagonists, and the characteristics of the null-direction responses suggest that both normal and induced directionality originate from the same sources or mechanisms. Baclofen also induced orientation selectivity, but this was rarely observed.
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影响因子：
56.9
作者：
SLAUGHTER, MM;MILLER, RF
通讯作者：
MILLER, RF
鲶鱼视网膜内神经元网络的解剖。
影响因子：
2.5
作者：
Sakai,HM;Naka,KI
通讯作者：
Naka,KI
巴氯芬对泥犬视网膜中持续和瞬时细胞的不同影响。
影响因子：
2.5
作者：
Slaughter,MM;Bai,SH
通讯作者：
Bai,SH
鲶鱼视网膜内神经元网络的解剖。
影响因子：
2.5
作者：
Sakai,HM;Naka,KI
通讯作者：
Naka,KI
巴氯芬对泥巴犬视网膜瞬时神经元的影响：生电和网络作用。
影响因子：
2.5
作者：
Bai,SH;Slaughter,MM
通讯作者：
Slaughter,MM