Basic research on cellular mechanisms of circadian oscillators in vertebrates.

脊椎动物昼夜节律振荡器的细胞机制的基础研究。

基本信息

批准号：
06660383
负责人：
MURAKAMI Noboru
金额：
$ 1.28万
依托单位：
Miyazaki University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1995
项目状态：
已结题

项目摘要

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

1.我们比较了体外培养的日本鹌鹑、鸽子和家麻雀松果体细胞褪黑素释放的昼夜节律振荡，在所有松果体细胞培养物中，昼夜节律在黑暗时期增加，在光照时期减少。褪黑激素的释放在鸽子和麻雀松果体细胞中持续长达 3-4 个周期，但在日本鹌鹑细胞中则不然。这些结果强化了禽类细胞中褪黑激素释放的论点。松果体在昼夜节律组织中的作用因物种而异。2.80S核糖体蛋白合成抑制剂茴香霉素的六小时脉冲诱导褪黑激素释放的昼夜节律振荡的稳态和相位依赖性相移。发生相位提前和延迟。分别在昼夜节律时间 (CT) 7.9 小时和 CT18.6 至 4.5 小时之间。这些结果表明，80S核糖体蛋白合成参与了鸽子松果体细胞中昼夜节律振荡器的正常和光训练功能。3.当失明的大鼠从笼子中转移出来时，跑步将轮子换成没有跑轮的笼子，自由跑节律的 tau 值延长。IGL 的完全损伤延长了轮跑活动节律的 tau 值，但运动活动的 tau 值却没有延长。当 IGL 损伤的大鼠从有跑轮的笼子转移到没有跑轮的笼子时，没有观察到进一步的变化，这些结果表明自由跑轮的日常活动改变了 tau。 -跑步，但不是通过运动活动，并且IGL可能参与了这种修改。4.我们检查了通过皮下植入的硅橡胶管连续施用褪黑激素是否加速了昼夜节律的重新调整改变照明周期的运动活动，并发现携带充满褪黑素的硅橡胶植入物的大鼠比携带空植入物时重新进入提前或延迟明暗周期的相移所需的时间更少。这些结果表明连续给药。褪黑激素加速昼夜运动活动节律重新进入新的明暗周期。