鞘内注射p-MPPF对异氟烷镇痛作用的影响

目的探讨异氟烷(isoflurane,Iso)镇痛作用与小鼠脊髓5-HT1A受体的关系。方法昆明种小鼠腹腔注射Iso建立镇痛模型。分别以甩尾法、热板法、醋酸扭体法(15min内)评估小鼠鞘内注射5-HT1A受体拮抗剂p-MPPF(6μg和3μg)对Iso镇痛作用的影响。结果单独鞘内注射p-MPPF对小鼠甩尾潜伏期、热板痛阈、扭体次数无影响(P>0.05)。与Iso镇痛组(Iso组)相比,合用药组(Iso+M6组,Iso+M3组)甩尾潜伏期与热板痛阈均缩短(P<0.01或P<0.05);Iso+M6组扭体次数较Iso组增多(P<0.05),Iso+M3组无变化(P>0.05)。结论 Iso体表镇痛作用与激动小鼠脊髓5-HT1A受体密切相关。

Influence of intrathecal injection of p-MPPF on the analgesic effects of isoflurane

Aim To investigate the relationship be-tween the analgesic effects of isoflurane ( Iso) and the 5-HT1A receptor in the spinal cord of mice. Methods After the analgesic model of mice was established by intraperitoneal injection ( ip) of Iso,tail-flick test,hotplate test and acetic-acid-writhing test ( during 15 minutes) were used respectively to observe the influence of intrathecal administration 6 μg or 3 μg p-MPPF ( an antagonist of 5-HT1A receptor) on the analgesic effects of Iso. Results Intrathecal administration of p-MPPF alone had no effects on tail-flick latency ( TFL) ,pain threshold in hot-plate test ( HPPT) or writhing times ( WTs) ( P > 0. 05) . Compared with Iso analgesic group ( Iso group) ,the TFL or HPPT of co-administration groups ( Iso + M6 group,Iso + M3 group) shortened ( P <0. 01 or P < 0. 05) ; the WTs of Iso + M6 group increased ( P < 0. 05) whereas that of Iso + M3 group was similar to Iso group ( P > 0. 05) . Conclusion These findings suggest that the surface analgesic effects of Iso are closely related to the excited 5-HT1A receptor in the spinal cord of mice.