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 光孔径，调节和血液流向的调节 视网膜。 这条通路中的自主神经节细胞的胞体是 位于睫状神经节。 所有的睫状体中的突触前末梢 神经节起源于中脑的Edinger-Westphal核。 乙酰胆碱，包含在这些终端，是唯一被证明 神经节中的神经递质，作用于烟碱受体， 突触后神经节细胞 最近，P物质样和亮氨酸脑啡肽样免疫反应性 在大多数这些细胞中， 在鸟类睫状神经节的胆碱能末梢，这表明，这些 神经活性肽沿着乙酰胆碱随神经传导释放 刺激. 这些肽在神经传递中的作用， 目前还不知道有一种眼科系统，本提案将对此进行研究。 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。 P物质的影响， 亮氨酸脑啡肽将通过应用这些和相关的 缩氨酸 纳洛酮，一种特异性阿片类拮抗剂，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种不同类型的突触后神经元。 细胞，睫状和脉络膜神经元，这可以很容易地刺穿 玻璃微电极 此外，突触前末梢形成 睫状神经元上的大的杯状末梢也可以成功地 被刺穿了 因此，突触前和突触后元件都可以研究 在这个神经节里 刺入突触前和突触后的能力 在鸡睫状神经节的元素是至关重要的 项目，因为目前的神经活性肽很可能对 神经节突触的两侧 量子尺寸和量子含量 也将在暴露于神经活性肽之前和期间测定。 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，学生的状况 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 the regulation of blood flow to 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. Recently, substance P-like and leucine-enkephalin-like immunoreactivities have been localized within dense core vesicles in a majority of these 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. Naloxone, a specific opioid antagonist, 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, which can be readily impaled by glass microelectrodes. In addition, presynaptic terminals which form large, calyciform endings on the ciliary neurons can also be successfully impaled. Thus, both presynaptic and postsynaptic elements can be studied in this ganglion. The ability to impale both presynaptic and postsynaptic elements in the chick ciliary ganglion is of critical importance to the project, since the neuroactive peptides present may well have effects on both sides of the ganglionic synapse. Quantal size and quantal content will also be determined before and during exposure to neuroactive peptides. 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.