Photoperiodic Changes in Aggression

攻击性的光周期变化

• 批准号: 0919911
• 负责人: Gregory Demas
• 金额: $ 30万
• 依托单位: Indiana University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2014-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0919911&HistoricalAwards=false
• 关键词: Photoperiodic; Changes; Aggression

Most animals experience large fluctuations in environmental conditions across the seasons of the year. Consequently, many animals display seasonal changes in physiology and behavior which allow them to cope with seasonal changes. Day length is the main environmental cue used by animals to coordinate seasonal behavioral and physiological responses. For example, animals living in long "summer-like" day lengths will maintain high levels of the hormone testosterone and thus will continue to breed, whereas animals housed on short "winter-like" days will inhibit their breeding due to low testosterone. In addition, it has recently been demonstrated that rodents housed in short days display increased aggression compared with animals housed on long days, despite lower levels of testosterone. This finding is particularly interesting given the traditional belief that testosterone regulates aggression. The goal of this project is to investigate the hormone mechanisms regulating seasonal changes in aggression in rodents. Specifically, animals will be housed in long or short days in the lab and levels of specific hormones, including the androgen DHEA and melatonin, will be examined. Aggression will then be videotaped and quantified using a computer-based video analysis system. Based on previous research, it is predicted that the short days will increase aggression and that both DHEA and melatonin play a role in mediating seasonal aggression. These experiments challenge the simple notion that all forms of aggression are testosterone-dependent and have important implications for the study of how hormones act on the brain to regulate social behaviors and how these behaviors may be altered by the environment. Collectively, these studies will help identify important and novel mechanisms of hormonal control of aggression. Importantly, these studies will provide excellent opportunities for both graduate and undergraduate students, including under-represented minorities, to gain hands-on experience and to allow them to develop important scientific skills by conducting, presenting and publishing scientific research.

大多数动物在一年中的各个季节都会经历环境条件的巨大波动。因此，许多动物的生理和行为表现出季节性变化，这使它们能够应对季节性变化。日长是动物用来协调季节性行为和生理反应的主要环境线索。例如，生活在“类似夏季”的长日照中的动物将保持高水平的睾酮激素，因此将继续繁殖，而生活在“类似冬季”的短日照中的动物会因睾酮水平低而抑制其繁殖。 此外，最近的研究表明，尽管睾丸激素水平较低，但与长期饲养的动物相比，短期饲养的啮齿动物表现出更强的攻击性。鉴于睾丸激素调节攻击性的传统观念，这一发现特别有趣。该项目的目标是研究调节啮齿动物攻击性季节性变化的激素机制。具体来说，动物将被关在实验室里长或短的日子，并检查特定激素的水平，包括雄激素 DHEA 和褪黑激素。然后，攻击行为将被录像并使用基于计算机的视频分析系统进行量化。根据之前的研究，预计较短的白天会增加攻击性，而 DHEA 和褪黑激素都在调节季节性攻击性中发挥作用。这些实验挑战了所有形式的攻击行为都依赖于睾酮的简单观念，并且对于研究激素如何作用于大脑以调节社会行为以及这些行为如何被环境改变具有重要意义。总的来说，这些研究将有助于确定激素控制攻击性的重要且新颖的机制。重要的是，这些研究将为研究生和本科生（包括代表性不足的少数族裔）提供绝佳的机会，让他们获得实践经验，并通过开展、展示和发表科学研究来培养重要的科学技能。