Multiple Actions of Pheromonal Bile Acids in Reproduction of the Sea Lamprey

信息素是一种化学分子，由动物物种的某些个体释放，并引起同一物种其他个体的行为、生理或发育变化。诱导行为改变的信息素受到了最多的关注。海七鳃鳗（Petromyzon marinus）就是这样一个例子，它是一种无颌鱼类的祖先。有充分的证据表明，性成熟的雄性七鳃鳗释放一些胆汁酸，吸引性成熟的雌性七鳃鳗到交配地点。最近，进一步的研究表明，这些胆汁酸还可以诱导不成熟的七鳃鳗更快地成熟。本研究假设胆汁酸信息素信号从嗅觉器官（鼻子）传递到下丘脑（中枢神经系统中具有生殖调节作用的一部分），诱导性成熟和生殖调节激素的产生和释放增加。为了验证这一假设，未成熟的七鳃鳗将暴露在天然和合成的信息素中。他们的大脑将被检查，以确定信息素激活的神经通路，以及随后使用神经生物学和分子生物学方法的生殖激素产生的变化。从这项研究中收集的数据可能会阐明信息素信号在中枢神经系统中传递的机制过程，并将记录信息素刺激下激素产生和释放的变化程度。该项目的预期结果可能对五大湖的一种入侵害虫——海七鳃鳗的管理产生重大影响。在这些研究期间，研究生和本科生将获得独特的培训机会，来自umatila部落的研究生和可能的实习生也将参与这些研究活动。

Pheromones are chemical molecules that are released by certain individuals of an animal species and that induce changes of behavior, physiology or development in other individuals of the same species. Pheromones that induce behavioral changes have received most attention. One such example can be found in the sea lamprey (Petromyzon marinus), an ancestral jawless fish. It is well documented that sexually mature male sea lampreys release some bile acids that attract sexually mature female sea lampreys to mating sites. Recently, further research has indicated that these bile acids may also induce less mature sea lampreys to mature faster. In this study, it is hypothesized that the bile acid pheromone signals are transmitted from the olfactory organ (nose) to the hypothalamus (a part of the central nervous system with a role in regulation of reproduction) to induce an increase in the production and release of hormones that regulate sexual maturation and reproduction. To test this hypothesis, immature sea lampreys will be exposed to natural and synthetic pheromones. Their brains will be examined to determine the neural pathways activated by the pheromone and the subsequent changes in reproductive hormone production using a combination of neurobiological and molecular biological approaches. It is likely that the data collected from this study will elucidate the mechanistic processes whereby pheromone signals are transmitted in the central nervous system and will document the extent of changes in hormone production and release in response to pheromone stimulation. Anticipated results from this project may have significant implications for the management of the sea lamprey, an invasive pest species in the Great Lakes. Graduate and undergraduate students will be offered unique training opportunities during these studies and a graduate student and possible interns from the Umatilla tribe will also be involved in these research activities.