Control of Seasonal Breeding in American Tree Sparrows

美国树麻雀季节性繁殖的控制

• 批准号: 9104722
• 负责人: Fred Wilson
• 金额: $ 13.8万
• 依托单位: Kansas State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-09-01 至 1994-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9104722&HistoricalAwards=false
• 关键词: Control; Seasonal; Breeding; American; Tree

Testicular growth in American tree sparrows occurs in spring in response to increasing daylength. By early summer, male tree sparrows become unresponsive to long days (i.e., they become photorefractory), and their testes regress. This project explores the physiological mechanisms that turn seasonal breeding on and off. The first phase tests the hypotheses that (1) a thyroid hormone (T4) simulates longs days (and thyroidectomy, short days), and (2) for photorefractoriness to be induced, T4 must be available when male tree sparrows experience long days. The second phase examines the hypothesis that brain receptors for excitatory amino acids (e.g., L-glutamate) transmit processes photic information (from brain photoreceptors, the biological clock, and/or elsewhere) to neurons that control the secretion of reproductive hormones from the pituitary gland. The ultimate goal of the project is to strengthen and extend understanding of the physiological basis of seasonal reproduction.//

美国树麻雀的睾丸生长发生在春季， 对日长增加的反应。 到了初夏，雄树 麻雀变得对长日照无反应（即，他们成为 光不应的），并且它们的睾丸退化。 该项目探索 开启季节性繁殖的生理机制， 关闭. 第一阶段测试的假设，（1）甲状腺 激素（T4）模拟长日（和甲状腺切除术，短日）， （2）要诱导光不应性，必须有T4 雄性树麻雀经历漫长的白天 第二阶段 检验了大脑兴奋性氨基酸受体 酸（例如，L-谷氨酸）传递光信息 (from大脑光感受器、生物钟和/或其他地方） 到控制生殖激素分泌的神经元 脑下垂体 该项目的最终目标是 加强和扩大对生理基础的理解， 季节性繁殖。