PHOTOPERIODIC CONTROL OF OBESITY

这些实验的目标是确定关键因素 参与对身体季节性变化的光周期控制 以及仓鼠的脂肪质量、新陈代谢和能量消耗。 叙利亚(Mesocrictus)体重的季节变化 金黄地鼠)和西伯利亚仓鼠 完全反映为屠体脂肪的变化。这些自然是- 在这些动物中，脂肪质量发生的变化是有趣的 因为，尽管这两个物种表现出相同的季节性 生殖反应，它们在身体上表现出相反的变化 体重和脂肪对相同的环境刺激(白天)， 由相同的神经内分泌转导因子(松果体和 其荷尔蒙，褪黑激素)。提出了三套实验方案。 第一组实验将描述 脂代谢及其潜在机制，包括 白色和棕色脂肪组织区域性变化的测量方法 脂肪生成和脂解，以及交感神经的参与 神经系统在这些过程中的作用。 第二组实验将考察对 西伯利亚仓鼠的体重、脂肪质量和代谢 特别是恢复身体和脂肪质量，脂肪组织 饥饿导致体内细胞减少后细胞数量的变化 体重和脂肪组织的手术切除(脂肪切除) 在身体的增重和减重两个阶段进行 重量循环。 第三组实验将探索是否有可能 褪黑素直接影响金黄地鼠脂肪细胞代谢 被光周期改变的“次级激素” (褪黑素)，进而影响身体和脂肪质量的变化，由于 白天的变化。光周期引起胰岛素的变化， 糖皮质激素和甲状腺激素将被记录在案，以及 被实验操纵以模拟循环水平 与与光周期相反的光周期相关联 动物被安置在屋里。脂质质量和新陈代谢的变化将 被监视。 这种多学科方法(利用概念和技术 从内分泌学、生物化学、神经科学、动物学和 心理生物学)应该提供有关季节性的新信息 对体重、脂肪和脂类代谢的影响 反映开发、维护中的基本流程 和逆转肥胖症。

The goal of these experiments is to determine the critical factors involved in the photoperiodic control of seasonal changes in body and lipid mass, metabolism, and energy expenditure in hamsters. The seasonal changes in body weight in Syrian (Mesocricetus auratus) and Siberian (Phodopus sungorus sungorus) hamsters are reflected entirely as changes in carcass lipid. These naturally- occurring changes in lipid mass are interesting in these animals because, although both species show the same seasonal reproductive responses, they show opposite changes in body weight and fat to the same environmental stimulus (daylength), mediated by the same neuroendocrine transducer (pineal gland and its hormone, melatonin). Three sets of experiments are proposed. The first set of experiments will describe the seasonal changes in lipid metabolism and their underlying mechanisms, and include measures of regional changes in white and brown adipose tissue lipogenesis and lipolysis, and the involvement of the sympathetic nervous system in these processes. The second set of experiments will examine the "regulation" of body weight, lipid mass and metabolism in Siberian hamsters, in particular the recovery of body and lipid mass, and adipose tissue cellularity changes following starvation-induced decreases in body weight, and the surgical removal of adipose tissue (lipectomy) performed during both the weight gain and loss phases of the body weight cycle. The third set of experiments will explore the possibility that melatonin directly affects hamster fat cell metabolism and that "secondary hormones" that are altered by the photoperiod (melatonin), in turn affect body and lipid mass changes due to changes in the daylength. Photoperiod induced changes in insulin, glucocorticoids and thyroid hormones will be documented, and experimentally manipulated to mimic the circulating levels associated with the photoperiod opposite to the photoperiod the animals are housed in. Changes in lipid mass and metabolism will be monitored. This multidisciplinary approach (utilizing concepts and techniques from endocrinology, biochemistry, neurosciences, zoology and psychobiology) should provide new information about the seasonal influences on body weight, fat, and lipid metabolism that may reflect fundamental processes in the development, maintenance and reversal of obesity.