Analysis of circadian clock mechanism and light-entarinmet in photoreceptor and circadian osilator cells in a higher animals.

地球上所有的生物都暴露在由地球自转和自转产生的周期性环境因素中。它们有一个生物钟来适应这些循环环境。这种生物钟调节各种生理功能的昼夜节律。鸟类松果体具有生物钟、光感受器和褪黑素的合成能力，这三个部分共同构成了鸟类的生理节律。因此，人们一直认为褪黑激素调节生物节律。褪黑素可使家雀和日本鸣禽的体温降低，活动受抑。这些结果表明松果体在夜间分泌褪黑素，抑制运动，降低体温，导致休息时间。我们发现GH刺激素Ghrelin是食物摄取的有力刺激因素，而神经梅毒素U是食物摄取的抑制因素。因此，我们研究了它们对生物钟的影响。神经递质U以时间依赖的方式引起昼夜节律的相移。此外，免疫组织化学显示神经梅毒素U的免疫染色细胞位于视交叉上核，为昼夜节律振荡器。这些结果表明，神经梅毒素U可能参与食物摄入量的调节和昼夜振荡系统的调节。

The all living organisms in the earth are exposed to cyclic environmental factors which are produced by earth's rotation and revolution. They had a biological clock to adapt to these cyclic environments. This biological clock regulate the circadian or circanual rhythms of various physiological functions. The purpose of this study is to examine how circadian clock regulate the physiological rhythm, and to examine the relationship between the circadian oscillator and regulator of food intake.The avian pineal gland posses the circadian clock, photoreceptor and melatonin synthetic capacity, and these three components are rinks all together. Therefore it has been assumed that melatonin regulate the biological rhythm. The administration of melatonin caused decrease of body temperature and inhibition of locomotor activity in house sparrow and Japanese quail. These results suggest that melatonin secretion from pineal gland during night time inhibits the locomotor activity and decrease body temperature, results in resting time.We discovered that ghrelin, a GH stimulating hormone, is a potent stimulator of food intake, and that neuromedin U is a inhibitor of food intake. Therefore, we examined the effect of them on the biological clock. The neuromedin U caused phase-shift of circadian rhythm in the time-dependent manner. Further, Immunohystochemistly revealed that immunostained cells for neuromedin U locate in suprachiasmatic nucleus which is circadian oscillator. Theses results indicate that neuromedin U may be involved in both regulation of food-intake and circadian oscillation system.