Basic research on cellular mechanisms of circadian oscillators in vertebrates.

1.我们比较了日本鹌鹑、鸽子和家雀体外培养松果体细胞褪黑素释放的昼夜节律振荡。在所有的松果体细胞培养中，褪黑素的释放在黑暗期增加，在光明期降低。在DD条件下，鸽子和家雀松果体细胞中褪黑素释放的昼夜节律持续了3-4个周期，而鹌鹑细胞则没有。这些结果加强了鸟类松果体在昼夜节律组织中的作用在物种之间存在差异的观点。作为一种80S核糖体蛋白合成抑制剂，6小时的大霉素脉冲可诱导褪黑激素释放昼夜节律振荡的稳态和相依赖相移。相位提前和延迟分别发生在昼夜节律时间（CT） 7.9h和CT18.6 - 4.5h之间。此外，大霉素阻断了光诱导的相推进。这些结果表明，80S核糖体蛋白的合成参与了鸽子松果体细胞昼夜节律振荡器的正常和轻度调控功能。当盲鼠从一个有跑步轮的笼子转移到一个没有跑步轮的笼子时，自由奔跑节奏的tau延长了。IGL的完全损伤延长了轮跑活动节律的tau，但没有延长运动活动节律。当igl病变的大鼠从一个有跑步轮的笼子转移到一个没有跑步轮的笼子时，没有观察到进一步的变化。这些结果表明，自由跑动节律的tau蛋白受到日常轮式跑动活动的影响，而不受运动活动的影响，IGL可能参与了这种影响。我们研究了通过皮下植入硅橡胶管持续给药褪黑激素是否会加速运动活动的昼夜节律对移位照明周期的重定向，并发现当大鼠携带充满褪黑激素的硅橡胶植入物时，与携带空植入物时相比，大鼠需要更短的时间来重定向到光-暗周期的提前或延迟相移。这些结果表明，持续给药褪黑激素加速了昼夜运动活动节奏的重新调频到一个新的光-暗周期。少

1.We compared the circadian oscillation of melatonin release from cultured pineal cells in Japanese quail, pigeon and house sparrowin vitro. Melatonin release increased during the dark period and low during the light period in all pineal cell cultures. Under DD conditions, the circadian rhythm of melatonin release persisted for up to 3-4 cycles in pigeon and house sparrow pineal cells, but not Japanese quail cell. These results strengthen the argument that the avian pineal gland's role in circadian organization differs between species.2.Six-hour pulses of anisomycin, an inhibitor of 80S ribosomal protein synthesis, induced steady atate and phase-dependent phase shifts of the circadian oscillation of melatonin release. The phase advances and delays occurred at circadian time (CT) 7.9h and between CT18.6 and 4.5h, respecitively. Furthermore, anisomycin blocked the light-induced phase advance. These results suggest that 80S ribosomal protein synthesis is involved in the normal and light-e … More ntrainment functions of the circadian oscillator in pigeon pineal cells.3.When blind rats were transferred from a cage with a running wheel to a cage without a running wheel, the tau of free-running rhythm lengthened. A complete lesion of the IGL lengthened the tau of the wheel-running activity rhythm, but not, locomotor activity rhythm. When IGL-lesioned rats were transferred from a cage with a running wheel to a cage without a running wheel, no further change was observed. These results indicate that the tau of the free-running rhythm is modified by a daily activity of wheel-running, but not by locomotor activity, and that the IGL may be involved in this modification.4.We examined whether continuous melatonin administration through subcutaneously implanted silastic tubing accelerates reentrainment of circadian rhythms of locomotor activity to shifted illumination cycles, and found that rats required less time to reentrain to an advance or delay phase shift of a light-dark cycle while carrying a silastic implant filled with melatonin than while carrying an empty implant. These results suggest that continuous administration of melatonin accelerates reeentrainment of the circadian locomotor activity rhythm to a new light-dark cycle. Less