Starter Grant: Role of Photoperiod, the Pineal Gland, and Melatonin on Compensatory Gonadal Hypertrophy in the Marsh Rice Rat (Oryzomys Palustris)

本研究旨在探讨光周期、昼夜节律系统、褪黑激素、松果体和食物摄入量在调节光周期啮齿动物--沼泽水稻鼠(Oryzomys Palustris)代偿性腺肥大(CGH)中的作用。当手术切除一个性腺导致剩余性腺的大小急剧增加时，就会导致代偿性性腺肥大。研究将在半去势的雄性和雌性沼泽水稻老鼠身上进行，这些老鼠被安置在不同的光周期制度或褪黑素处理条件下。埃德蒙兹博士还将通过进行“共振”实验来检验CGH在多大程度上受到昼夜节律系统的调节。由于CGH只在实验室的啮齿动物品系中进行了研究，因此这项工作对于发现光周期对CGH的影响是重要的。这项工作的结果可能为深入了解CGH的潜在机制以及褪黑素治疗对CGH过程的可能影响提供依据。

Lay Abstract EDMONDS, Kent 98-128224 The goals of the proposed studies are to examine the roles of photoperiod, the circadian system, melatonin, the pineal gland, and food intake in regulating the magnitude of compensatory gonadal hypertrophy (CGH) in a reproductively photoperiodic rodent, the marsh rice rat (Oryzomys palustris). Compensatory gonadal hypertrophy results when the surgical removal of one gonad produces a dramatic increase in the size of the remaining gonad. Studies will be conducted on hemi-castrated male and female marsh rice rats housed under different photoperiodic regimes, or melatonin treatment conditions. Dr. Edmunds will also examine the extent to which CGH is mediated by the circadian system by conducting "resonance" experiments. Because CGH has only been studied in laboratory strains of rodents, this work is important to discover the effects of photoperiod on CGH. The results of this work may provide insights into the mechanisms underlying CGH and the possible ramifications of melatonin treatment on CGH processes.