社会与工程心理学研究室知识库

    利用经典条件反射性免疫抑制动物模型，以新异味觉刺激糖精水作为条件刺激，免疫抑制剂环磷酞胺为非条件刺激，观测两次条件结合训练后，再次呈现条件刺激诱发条件反射性细胞免疫功能抑制作用的动态改变，获得味觉厌恶性条件刺激和条件反射性免疫抑制表达和保持的时程特点。在此基础上，采用c-fos作为探针，进一步观察不同时程再次条件刺激诱发条件反射性免疫抑制反应时脑内相关核团FOS蛋白表达情况。通过不同时程脑内FOS蛋白表达比较获得分别与条件发射性免疫抑制和味觉厌恶性条件反射相关的脑区。结果表明，条件反射性免疫抑制作用在训练后第5天较强，第30天基本消失，而味觉厌恶性条件反射始终稳定保持到第30天。FOS蛋白表达的结果显示，下丘脑室旁核、视上核、弓状核、杏仁基底内侧核中FOS蛋白表达在第5天较强，而第30天几乎没有表达，与细胞免疫功能改变在时程和趋势上具有一致性。杏仁中央核、岛颗粒皮质中FOS蛋白在第5天表达较密集，第30天仍有密集的FOS蛋白表达，但与第5天比较明显减弱。无论第5天还是第30天再次给予CS，在条件刺激组和糖精水对照组的下丘脑背内侧核、乳头体上核、岛无颗粒皮质、岛乱颗粒皮质、杏仁基底外侧核内均可见到FOS蛋白表达。通过FOS蛋白表达时程的差异比较，提示下丘脑室旁核、视上核、弓状核及杏仁基底内侧核可能CNS内介导CS诱导的免疫抑制效应的重要核团。岛颗粒皮质和杏仁中央核既参与CIS的免疫抑制的调节，也与味觉厌恶性条件反射的产生有关。下丘脑背内侧核、乳头体上核、岛无颗粒皮质、岛乱颗粒皮质、杏仁基底外侧核可能仅与味觉厌恶性条件发射的形成和保持有关。

    Conditioned immunosuppression (CIS) using a taste aversion paradigm(CTA) has been demonstrated in a number of laboratory models, but little is known about the central mechanisms of CIS. By using c一fos protein production as a marker of neuronal activation, the present work att}.mpts to localize the brain regions involved in the neural mechanism of CIS. CTA and CIS were established by intake of saccharin as the conditioned stimulus (CS) with an injection of cyclophosphamide as an unconditioned stimulus (UCS). After animals were reexposed to CS alone at intervals of 5 or 30 days after two trials of CS-UCS pairing, both CTA and CIS- were assessed and the expression of c一s protein in the brain was also observed correspondingly. The results showed that CTA occurred on both day 5 and day 30 after conditioning but CIS occurred only on day 5 after conditioning. Furthermore, it was found that intensive c一s expression in .the hypothalamus paraventricular nucleus (PVN),the amygdaloid central (Ce), the granular insular cortex(GI) in the CS group was observed at the 5 days interval and a few c一s immunoreactive inductions at the 30 days interval after re-exposure to CS. By comparing the results of the 5th day with the 30th day, it suggests that the PVN is an important nucleus related to the modulation of CIS, the Ce and GI are involved in CTA and CIS.