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，并在同一物种的其他个体中引起行为、生理或发育的变化。诱导行为变化的信息素受到了最多的关注。一个这样的例子可以在海鳗(Petromyzon Marinus)中找到，这是一种祖先的无颌鱼。有充分的证据表明，性成熟的雄性七鳃鳗会释放一些胆汁酸，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，这些胆汁酸还可能诱导不太成熟的七鳃鳗更快成熟。在这项研究中，假设胆汁酸信息素信号从嗅器官(鼻子)传递到下丘脑(中枢神经系统的一部分，起着调节生殖的作用)，以诱导调节性成熟和生殖的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信息素中。他们的大脑将通过神经生物学和分子生物学相结合的方法进行检查，以确定信息素激活的神经通路以及随后生殖激素产生的变化。这项研究收集的数据很可能将阐明信息素信号在中枢神经系统中传递的机制过程，并将记录激素产生和释放响应信息素刺激的变化程度。该项目的预期结果可能对五大湖的一种入侵有害物种--七鳃鳗的管理产生重大影响。在这些研究期间，将为研究生和本科生提供独特的培训机会，乌马提拉部落的一名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.