微电泳U—50488对大鼠疑核呼吸相关单位电活动的影响

本工作观察了微电泳给予 U-50488对大鼠延髓疑核呼吸相关单位自发放电活动的影响。在96个单位中,呈抑制效应的51个,兴奋效应的11个,先抑制后兴奋的3个,先兴奋后抑制的6个,其余25个单位的自发放电活动无明显变化。在16个 U-50488产生抑制效应的单位中,12个单位的抑制效应能被纳洛酮对抗。2个 U-50488 表现为兴奋效应的单位,纳洛酮也显出拮抗效应。U-50488产生抑制效应持续的时间明显长于兴奋效应持续的时间。本工作的结果提示,k 受体可能也参与呼吸调控作用,并且介导 U-50488抑制效应的阿片受体亚型可能不同于介导兴奋效应的阿片受体亚型。

EFFECTS OF MICROIONTOPHORETICALLY APPLIED U-50488 ON THE SPONTANEOUS DISCHARGES OF RESPIRATION RELATED UNITS(RRUs)IN THE REGION OF NUCLEUS AMBIGUUS OF RAT

In the present study,the effects of microiontophoretically applied U-50488on the spontaneous discharge of respitation related units(RRUs)in nucleus am-biguus of rats were observed.Of 96 RRUs recorded,U-50488 produced depressanteffect on 51 units,excitative effect on 11 units,excitation followed by depression on6 units,depression followed by excitation on 3 units.The remaining 25 units werenot influenced.Naloxone administered iontophoretically not only blocked U-50488-induced depression in 12 out of 16 units,but also blocked U-50488-inducedexcitation in 2 units.Duration of the depression produced by U-50488 was re-markably longer than that of excitation.The result suggested that kappa receptormight be involved in respiratory regulation and that the subtype of opiatereceptors which mediates depression and excitation effect might not be the same.