Onset mechanism of psychiatric disorders related to the biological clock abnormalities and their treatment

点击翻译按钮获取中文摘要

This research project team was organized to clarify what function of the biological clock is out of order in the diseases to which circadian rhythm abnormalities relate and what treatment would be effective for those disorders.1. Experimental research using animals. Using golden hamsters which have photoperiodism, evidence was established for their reactions to photoperiod are related to their experiences of having exposured to the light and their developmental stages. In rats changes in the living conditions had definitely alter their free-running period. Circadian rhyhtms of the pineal of the mother was transmitted to the pups by way of melatonin. Acrophase of the circadian rhythm delayed in rats kept in the dim light and shortened photoperiod, while it advanced by the treatment with photopulsations, thus these animals can be used as an animal model of the seasonal affective disorder.2. Basic research in humans. Evidence for the phase response curve to the light in humans was obtaine … More d by the experiments in which volunteers living in an isolation unit were observed their temperature rhythms longitudinally. Inter-individual difference in the melatonin secretion patterns to various light intensities was evident in the normal volunteers, and Orientals were commonly lower sensitivity to the light than Caucasians. Interval feeding in the severely ill patients unable to eat showed changes in the timing of feeding shifted the phase of their circadian rhythms of not only glucose and insulin levels but cortisol in plasma. This may suggest strong association of nutritional intake schedule with circadian rhythms. In children with severe brain damage had abnormalities of body temperature rhythm that suggests localization of the clock mechanism in the brain.3. Clinical Investigations. Multi-center collaborative survey was carried out for seasonal affective disorder in Japanese population. 46 suspected individuals were identified through investigation of population responded to mass media advertisemes. Relationship of onset of depressive episodes to the season, clinical features of this disorder were analyzed and comparison was made with previous data in other populations. Many similarities were noticed while sex ratio in Japanese population was rather low as 1:1.4 (m:f). Equipments for phototherapy were deviced and applied to these patients and proved to have efficacy. Phototherapy was found to be effective to other disorders such as senile dementias and sleep disorders. Deep body temperature rhythms were variablly disturbed in depression. Less