Department of Neuroscience and Physiology, State University of New York Upstate Medical University, Syracuse, New York 13210, USA.
Alcohol Clin Exp Res. 2010 Oct;34(10):1705-13. doi: 10.1111/j.1530-0277.2010.01257.x. Epub 2010 Jul 5.
Gestational ethanol exposure enhances the adolescent reflexive sniffing response to ethanol odor. Postnatal exposures of naïve animals as either an observer (i.e., conspecific) or demonstrator (i.e., intoxicated peer) using a social transmission of food odor preference paradigm also yields enhanced odor-mediated responses. Studies on the interaction of fetal and postnatal exposures using the social transmission paradigm have been limited to the responses of observers. When combined, the enhanced response is greater than either form of exposure alone and, in observer females, yields adult persistence. The absence of a male effect is noteworthy, given that chemosensory mechanisms are suggested to be an important antecedent factor in the progression of ethanol preference. Observers gain odor information on the breath of the demonstrator through social interaction. Demonstrators experience the pharmacologic properties of ethanol along with retronasal and hematogenic olfaction. Thus, we tested whether augmentation of the fetal ethanol-induced behavioral response with postnatal exposure as a demonstrator differed from that as an observer. We also examined whether re-exposure as a demonstrator yields persistence in both sexes.
Pregnant dams were fed an ethanol containing or control liquid diet throughout gestation. Progeny received four ethanol or water exposures: one every 48 hours through either intragastric infusion or social interaction with the infused peer beginning on P29. The reflexive behavioral sniffing response to ethanol odor was tested at postnatal (P) day 37 or P90, using whole-body plethysmography.
When tested in either adolescence or adulthood - fetal ethanol exposed adolescent ethanol observers and demonstrators significantly differed in their odor-mediated response to ethanol odor both between themselves and from their respective water controls. Nonetheless, adolescent ethanol re-exposure as a demonstrator, like an observer, enhanced the reflexive sniffing response to ethanol odor at both testing ages by augmenting the known effects of prior fetal ethanol experience. At each age, the magnitude of the enhanced odor response in demonstrators was similar to that of observers. Interestingly, only re-exposure as a demonstrator resulted in persistence of the behavioral response into adulthood in both sexes.
The method of ethanol re-exposure plays an important role in prolonging the odor-mediated effects of fetal exposure. While ethanol odor-specific exposure through social interaction is important, additional factors such as the pairing of retronasal and hematogenic olfaction with ethanol's intoxicating properties appear necessary to achieve persistence in both sexes.
胚胎乙醇暴露增强了青春期对乙醇气味的反射性嗅探反应。在使用社会传递食物气味偏好范式作为观察者（即同种动物）或示范者（即醉酒同伴）对新生动物进行的产后暴露也会产生增强的气味介导反应。使用社会传递范式研究胎儿和产后暴露的相互作用仅限于观察动物的反应。当两者结合时，增强的反应大于任何一种暴露形式单独作用的反应，并且在观察女性中，会导致成年期的持久性。男性没有产生影响是值得注意的，因为化学感觉机制被认为是乙醇偏好进展的一个重要先行因素。观察者通过社交互动从示范者的呼吸中获得气味信息。示范者经历乙醇的药理特性，以及逆行和血液嗅觉。因此，我们测试了胎儿乙醇诱导的行为反应与产后暴露作为示范者的增强是否与作为观察者的增强不同。我们还检查了作为示范者再次暴露是否会导致两性持久性。
在整个妊娠期，给怀孕的母鼠喂食含乙醇或对照的液体饮食。后代接受了四次乙醇或水暴露：从 P29 开始，每隔 48 小时通过胃内输注或与输注同伴的社交互动进行一次。使用全身 plethysmography 在产后（P）第 37 天或 P90 测试对乙醇气味的反射性嗅探反应。
在青春期或成年期测试时 - 胎儿乙醇暴露的青春期乙醇观察动物和示范者在对乙醇气味的气味介导反应方面与各自的水对照动物存在显著差异。尽管如此，青春期乙醇再次暴露作为示范者，就像作为观察者一样，通过增强先前胎儿乙醇暴露的已知影响，增强了对乙醇气味的反射性嗅探反应，从而增强了对乙醇气味的反射性嗅探反应。在每个年龄，示范者增强的气味反应的幅度与观察者相似。有趣的是，只有再次暴露作为示范者才能导致两性行为反应在成年期的持久性。
乙醇再暴露的方式在延长胎儿暴露的气味介导作用方面起着重要作用。虽然通过社会互动进行乙醇气味特异性暴露很重要，但其他因素，如逆行和血液嗅觉与乙醇的醉酒特性的结合，似乎是在两性中实现持久性所必需的。
