ROLE OF PEPTIDES IN OCULOMOTOR NEUROTRANSMISSION

眼神经通路的副交感神经成分负责 一些关键的非视网膜眼过程，包括控制 光孔、调节和调节视网膜的血流。 该通路中自主神经节细胞的胞体位于 睫状神经节 睫状神经节中的所有突触前终末 起源于中脑的Edinger-Westphal核 乙酰胆碱， 是唯一被证实的神经递质， 神经节，作用于突触后神经节细胞上的烟碱受体。 P物质样和亮氨酸脑啡肽样免疫反应性已被证实。 位于大多数胆碱能神经细胞的致密核心囊泡内， 终末在鸟类睫状神经节，这表明，这些神经活性 肽在神经刺激后与乙酰胆碱一起沿着释放。 这些肽在眼神经系统的神经传递中的作用是 我们不知道，并将在本报告中进行研究。 从鸡胚和孵化鸡中获得的完整睫状神经节 将在体外电生理室中进行研究。 细胞内和细胞外记录方法将用于 表征神经节中的非烟碱传递。 的影响 P物质和亮氨酸脑啡肽将通过应用这些 和相关肽。 特定的阿片类拮抗剂将用于揭示 任何内源性阿片类药物作用。 鸟类睫状神经节含有两个 不同类型的突触后细胞，纤毛和脉络膜神经元。 在 此外，突触前终末形成的杯状末端上的 睫状神经元可被刺穿在该神经节中。 能力记录 神经节中突触前和突触后神经元的神经传导是至关重要的 重要性的项目，因为我们已经表明，神经活性 存在的肽对神经节突触的两侧都有作用。 在脑切片制备中使用细胞内记录， 速激肽和阿片肽将在Edinger-Westphal 核，这是已知的接受P物质阳性神经支配，从 对侧视交叉上核 特别令人感兴趣的是 细胞核中的细胞体的肽反应与 睫状神经节内的终末。 这一建议应提供重要信息，说明 眼内突触传递中的内源性神经活性肽 通路 许多眼部临床疾病都涉及这方面的缺陷。 系统 其中包括住宿、内部 眼肌麻痹和强直性瞳孔。 此外，学生的情况 是许多眼部综合征的重要诊断标志， 头部外伤

The parasympathetic component of the oculomotor pathway is responsible for a number of critical non-retinal ocular processes, including control of the light aperture, accommodation and regulation of blood flow t the retina. The cell bodies of autonomic ganglion cells in this pathway are located in the ciliary ganglion. All presynaptic terminals in the ciliary ganglion originate in the midbrain in the Edinger-Westphal nucleus. Acetylcholine, contained within these terminals, is the only proven neurotransmitter in the ganglion, acting at nicotinic receptors on postsynaptic ganglion cells. Substance P-like and leucine-enkephalin-like immunoreactivities have been localized within dense core vesicles in a majority of the cholinergic terminals in the avian ciliary ganglion, suggesting that these neuroactive peptides are released along with acetylcholine following nerve stimulation. The role of these peptides in neurotransmission in the oculomotor system is not known and will be examined in this proposal. Intact ciliary ganglia obtained from chick embryos and hatched chickens will be studied in an in vitro electrophysiological chamber. Intracellular and extracellular recording methods will be used to characterize non-nicotinic transmission in the ganglion. The effects of substance P and leucine-enkephalin will be examined by application of these and related peptides. Specific opioid antagonists will be used to reveal any endogenous opioid actions. The avian ciliary ganglion contains two distinct types of postsynaptic cells, the ciliary and choroid neurons. In addition, presynaptic terminals which form calyciform endings on the ciliary neurons can be impaled in this ganglion. The ability to record from presynaptic and postsynaptic neurons in the ganglion is of critical importance to the project, since we have shown that the neuroactive peptides present have effects on both sides of the ganglionic synapse. Using intracellular recording in a brain slice preparation, the effects of tachykinins and opioid peptides will be examined in the Edinger-Westphal nucleus, which is known to receive a substance P-positive innervation from the contralateral suprachiasmatic nucleus. Of particular interest will be a comparison of the peptide responses of cell bodies in the nucleus to those of their terminals within the ciliary ganglion. This proposal should provide important information on the role of endogenous neuroactive peptides in synaptic transmission in the oculomotor pathway. A number of clinical diseases of the eye involve defects in this system. These include some defects in accommodation, internal ophthalmoplegia and tonic pupil. In addition, the condition of the pupil is an important diagnostic sign in numerous ocular syndromes and in traumatic injuries to the head.