8-OH-DPAT对大鼠体感皮质5-羟色胺抑制单位自发放电的抑制作用

INHIBITION OF 8-OH-DPAT ON SPONTANEOUS UNIT DISCHARGES OF 5-HYDROXYTRYPTAMINE INHIBITORY UNIT IN RAT PRIMARY SOMATOSENSORY CORTEX

目的:研究5-羟色胺(5-HT)对大鼠大脑皮质第一体表感觉区自发单位放电(SI-SUD)的影响,以及5-HT1A受体在5-HT抑制SI-SUD中的可能作用。方法:记录微电泳5-HT及5-HT1A受体选择性激动剂8-OH-DPAT前后的SI-SUD,分析:MISI-SUD的平均放电间隔(MISl)变化并作统计学处理。结果:①微电泳5-HT对SI-SUD的影响有3种情况:则MISI增大(抑制作用)(48/96);MISI减小(兴奋作用)(26/96)或MISI无明显改变(无明显影响)(22/96)。其中以抑制作用为主。②在20个5-HT抑制单位中,微电泳8-OH-DPAT可抑制其中17个单位的SI-SUD,而其余3个单位的SI-SUD无明显改变。结论:5-HT对SI-SUD的影响以抑制作用为主。体感皮质的大部分5-HT抑制单位存在有5-HT1A受体,并参与5-HT对SI-SUD的抑制作用。

Aim： To investigate the effect of 5-hydroxytryptamine（5-HT） on spontaneous unit discharges of primary somatosensory cortex （SI-SUD） and the role of 5-HT1A receptor in 5-HT inhibitory effect on SI-SUD in rat. Methods： The SI-SUD was recorded before and during microiontophoresis of 5-HT and 8-OH-DPAT（the selective agonist for 5-HTIA receptor. The changes of mean of interspike interval（MISI） of SI-SUD were analysed and handled with the statistics. Results： （3） Effects of 5-HT on SI-SUD may be inhibitory（48/96）, excitatory（26/96） or non-responsive（22/96）, and the major effect is inhibitory. OIn 20 of 5-HT inhibited units, 17 are also inhibited with microiontophoresis of 8-OH-DPAT, but 3 have no obvious response to 8-OH-DPAT. Conclusion： The major effect of 5-HT on SI-SUD is inhibitory. In majority of 5-HT inhibited units, 5-HTIA receptor may be existence, which may involve in the inhibition of 5-HT on SI-SUD.