FUNCTIONAL ROLE OF INDOLEAMINES IN THE MAMMALIAN RETINA

尽管生化和解剖学数据表明 5-羟色胺或相关的吲哚胺是体内 哺乳动物视网膜，我们对视网膜功能的理解 内源性吲哚胺极为有限。这一点的作用 将使用药物操纵来研究递质。 兔子的视网膜。一个孤立的超融合眼罩和一个 将使用完整的动脉灌流制剂进行研究 特异性5-羟色胺能拮抗剂对反应的影响 生理鉴定的神经节细胞。到目前为止的结果 点已表明吲哚胺拮抗剂减少 中心位置和偏离中心位置的响应都很快(X和Y) 神经节细胞。神经节细胞功能的其他几个方面将 现在请注意。 1.内源性吲哚胺在体内的作用是什么 阐述W细胞的感受场特性？ 具体地说，只影响道路上的道路，并且 吲哚胺对触发功能有任何贡献。(在 过去一个给定传送器的作用只有在以下情况下才被阐明 对这些W细胞进行了研究)。 2.内源性吲哚胺在明视中的作用 对镜视视网膜？积聚吲哚胺的神经元是 广泛连接到杆状双极电池，因此有可能 内源性吲哚胺在暗视中有特定的作用 视网膜。 3.内源性吲哚胺在 神经节细胞反应性和敏感性的调节？这个 先前工作中出现的假说表明 该变送器用于提高对增量的灵敏度 光的力量。这一假设将通过研究以下因素的影响来检验 5-羟色胺能药物对神经节反应性和敏感性的影响 细胞。 兔视网膜已被证明是一个有用的模型系统，在其中 开发关于发射器函数的泛化，这些函数具有 在其他视网膜和中枢神经系统的其他区域也被证明有效。 因此，阐明内源性吲哚胺在兔体内的作用 视网膜将有助于我们对视觉处理的理解 以及对5-羟色胺在体内的作用的理解 哺乳动物中枢神经系统。

Despite biochemical and anatomical data which indicate that serotonin or a related indoleamine is a transmitter in the mammalial retina, our understanding of the function of the endogenous indoleamine is extremely limited. The role of this transmitter will be studied using pharmacological manipulation of the rabbit retina. Both an isolated superfused eyecup and an intact arterially perfused preparation will be employed to study the effects of specific serotonergic antagonists on the responses of physiologically identified ganglion cells. Results up to this point have shown that indoleamine antagonists reduce ON responses in both ON center and OFF center brisk (X and Y) ganglion cells. Several other aspects of ganglion cell function will now be addressed. 1. What is the role of the endogenous indoleamine in the elaboration of the receptive field properties of W-cells? Specifically are only ON-pathways affected and does the indoleamine make any contribution to trigger features. (In the past the role of a given transmitter has been elucidated only when these W-cells were studied). 2. What is the role of the endogenous indoleamine in the photopic versus scoptic retina? The indoleamine-accumulating neuron is extensively connected to the rod bipolar cells, thus it is possible that the endogenous indoleamine has a specific role in scotopic retina. 3. What role does the endogenous indoleamine have in the modulation of ganglion cell responsivity and sensitivity? The hypothesis which has emerged from previous work suggests that this transmitter serves to increase the sensitivity to increments of light. This hypothesis will be tested by studying the effects of serotonergic drugs on the responsivity and sensitivity of ganglion cells. The rabbit retina has proven to be a useful model system in which to develop generalizations about transmitter function which have proven valid in other retinae and also other regions of the CNS. Thus, elucidating the role of the endogenous indoleamine in rabbit retina will contribute to our understanding of visual processing and to the understanding of the function of serotonin in the mammalian CNS.