中文摘要：

为了明确5-HI参与腹外侧眶皮层（VLO）的抗伤害效应以及VLO内的5-HI1A受体与该效应之间的关系，本研究采用浅麻大鼠，以甩尾反射潜伏期（TFL）为指标，观察VLO内微量注射5-HT和选择性5-HI1A受体拮抗剂p-MPPI对11FL的影响。结果显示：VLO内微量注射5-HT（2．0、5．0、10．0P,g）可剂量依赖性抑制辐射热诱发的TFL；而VLO内预先5min微量注射5-HT1A受体拮抗剂p-MPPI（0．2μg）可拈抗5-HT（10．0μg）诱发的抗伤害效应。本研究的结果提示5-HT参与VLO内的抗伤害效应，而该效应可能由5-HI1A受体介导。

英文摘要：

To examine the antinociceptive effects of 5-hydroxytryptamine （5-HT） in the ventrolateral orbital cortex （VLO） and the rela- tionship of 5-HT1A receptor and these antinociceptive effects, the light anaesthesia rats were used in the present study, and noxious heatevoked tail flick latencies （TFL） were measured as an index to observe the effects of microinjection of 5-HT and p-MPPI, a selective 5- HT1A receptor antagonist, on the TFL. The results showed that microinjection of 5-HT （2.0, 5.0, 10.0μg） into the VLO depressed the noxious heat-evoked TFL in a dose-dependent manner. Pretreatment 5 min with p-MPPI （0.2 μg） antagonized the 5-HT （10.0 μg）-evoked inhibition. These results suggest that 5-HT is involved in VLO antinociception and the effect is mediated by 5-HT1A receptor.