NITRIC OXIDE AND CIRCADIAN ORGANIZATION

描述（申请人？在没有环境时间线索的情况下， 动物在行为和生理上继续表现出每日周期， 约24小时。在哺乳动物中，这些节奏是内源性的， 由位于视交叉上方的双侧对称核产生， 视交叉上核（SCN）。直接视网膜下丘脑束（RHT）， 视网膜神经节细胞到SCN负责传输光 从视网膜到昼夜节律起搏器的信息， 使这些内源性节律与环境同步 光：暗循环。一个重要的问题是神经递质是什么 参与从视网膜到SCN的信号转导途径。的 本提案的目的是研究一氧化氮在 光诱导和昼夜节律组织。目前的建议有三个 具体目标：具体目标I：确定NO在SCN中的作用， 夹带具体目标II：了解神经解剖学关系， NO阳性细胞与SCN的其他已知细胞类型/组分。具体 目的III：阐明NO作为输出信号或作为SCN内信号的作用 协调信号，以调节昼夜运动节律。

DESCRIPTION (applicant?s abstract): In the absence of environmental time cues, animals continue to exhibit daily cycles in behavior and physiology with a period of approximately 24 h. In mammals, these rhythms are endogenously generated by bilaterally symmetric nuclei situated above the optic chiasm, the suprachiasmatic nuclei (SCN). A direct retinohypothalamic tract (RHT) from retinal ganglion cells to the SCN is responsible for transmitting light information from the retina to the circadian pacemaker to allow animals to entrain (synchronize) these endogenous rhythms with the environmental light:dark cycle. An important question is what neurotransmitter(s) are involved in the signal transduction pathway from the retina to the SCN. The goal of the present proposal is to investigate the role of nitric oxide in photic entrainment and circadian organization. The present proposal has three specific aims: Specific Aim I: To determine the role of NO in the SCN in photic entrainment. Specific Aim II: To understand the neuroanatomical relationship of NO-positive cells to other known cell types / components of the SCN. Specific Aim III: To clarify the role of NO as an output signal, or as an intra-SCN coordination signal, to modulate circadian locomotor rhythms.