Using the Peptide Hormone Conopressin to Characterize a Reproductive Central Pattern Generator

激素对行为有很强的影响。例如，性激素雌激素和睾丸激素是造成男性和女性行为差异的主要原因。克里斯坦实验室研究激素如何启动和控制行为。为了精确地理解这些机制，他们研究了一种动物，药用水蛭，它用相对简单的神经系统产生各种复杂的行为。通过研究对游泳、爬行和进食的控制，他们阐明了水蛭如何产生行为并在其中做出选择。从这些研究中获得的理解为包括人类在内的更复杂动物的实验提供了信息，这些实验采用相同的机制来决定可能的行为反应。Kristan小组将使用相同的电生理学，药理学和行为学技术，这些技术在理解行为选择方面非常成功，以研究激素对行为调节的细胞基础。他们将确定加压素的类似物如何引起药用水蛭的求偶、交配和产卵。加压素是一种广泛分布于动物界的肽类激素。从蜗牛到人类，所有动物都使用加压素来诱导和改变生殖和养育行为。用血管加压素的同系物治疗水蛭能可靠地增强水蛭的生殖行为。Kristan组将在康诺加压素治疗前和治疗期间表征神经系统的活性。他们的研究将展示这种激素如何导致单独识别的神经元改变它们的活动，并诱导动物产生成功繁殖所必需的行为，从而延续物种。该项目从一开始就主要由本科生进行，该项目的一个主要组成部分将继续为这些学生提供参与尖端研究的机会。

Hormones have strong effects on behavior. The sex hormones estrogen and testosterone, for example, are responsible for major differences in the behaviors of men and women. The Kristan laboratory studies how hormones initiate and control behavior. To get a precise understanding of these mechanisms, they work with an animal, the medicinal leech, which produces a variety of complex behaviors with a relatively simple nervous system. Studying the control of swimming, crawling, and feeding, they have elucidated how leeches produce behaviors and choose among them. Understanding gained from these studies has informed experiments on more complex animals, including humans, which employ the same mechanisms to decide among possible behavioral responses. The Kristan group will use the same electrophysiological, pharmacological, and behavioral techniques that have proven so successful for them in understanding behavioral choice to study the cellular basis for behavioral modulation by hormones. They will determine how an analog of vasopressin causes courtship, copulation, and egg deposition in medicinal leeches. Vasopressin is a peptide hormone that is broadly distributed across the animal kingdom. All animals, from snails to humans, use vasopressin to induce and modify reproductive and parenting behaviors. Treating leeches with a homologue of vasopression reliably elicits leech reproductive behavior. The Kristan group will characterize activity in the nervous system before and during conopressin treatment. Their studies will show how this hormone causes individually identified neurons to change their activity and induces the animal to produce the constellation of behaviors that are essential for successful reproduction and, thereby, the continuation of the species. This project, from its beginning, has been conducted primarily by undergraduates, and a major component of the project will continue to give these students an opportunity to take part in cutting-edge research.