MODULATION OF A δ-AND C-FIBER EVOKED RESPONSES OF NOCICEPTIVE NEURONS IN THE SUPERFICIAL AND THE DEEPER DORSAL HORN OF THE MEDULLA:ROLE OF OPIOID RECEPTORS(μ, δ_1, δ_2)

作     者：王小民 

出 版 物：《Journal of Pharmaceutical Analysis》 (药物分析学报（英文版）)

年 卷 期：1995年第9卷第2期

页      面：202-203页

学科分类：0710[理学-生物学] 07[理学] 071006[理学-神经生物学] 

主　　题：pain trigeminal dorsal horn opioid receptor DPDPE DELT DAMGO NTB BNTX naloxone 

摘      要：The present study was designed to investigate the effects of intravenously administered agonists and antagonists at μ(DAMGO, naloxone,)δ1 (DPDPE,BNTX)andδ2(DELT, NTB)opioid receptors on the Aδ-and C-fiber evoked responses of nociceptive neurons in the superficial and the deeper dorsal horn of the rat *** single unit recording were made from 70 nociceptive neurons(28 NS,42 WDR) in the superficial dorsal horn and 37 nociceptive neurons(4 NS,33 WDR)in the deeper dorsal *** these neurons had an ipsilateral orofacial mechanoreceptive field and majority of these neurons had no spontaneous activity. The latencies for the C fiber evoked responses ranged from 34～105 msec whereas for Aδfiber-evoked responses it ranged from 3～22msec. A clear separation was observed between early and late responses of evoked by Cand Aδ-*** of DPDPE,DELT and DAMGO produced inhibitory effects on the Aδ-and C-fiber evoked responses of nociceptive neurons in the superficial and thedeeper dorsal *** comparison,the inhibition was more pronounced on the C-fiber evoked response than on the Aδ-fiber evoked response,and DAMGO produced a stronger inhibitory action than both DELT and DPDPE. Additionally,DPDPE produced facilitation, or inhibition followed by facilitation on the Aδ-and C-response and the effect had longer latency and longer time *** also induced completely oppsite effects on the Aδ-and C-fiber evoked *** the facilitation was observed,the effect was not dose-dependent. Application of BNTX (0.4～1mg/kg),a δ1 receptor antagonist,produced antagonism of DPDPE in 88%(7/8) neurons. Application of the doses (0.7～1mg/kg) of BTB,δ2-receptor antagonist,resulted in antagonism of both DELT and DPDPE. The inhibition of DELT on Aδ-response was antagonized by doses (0.3～1mg/kg)of NTB in 100% (14/14)neurons while the antagonism on C-response was in 79%(11/14) *** effect produced by DPDPE was antagonized by the doses (0.7～1mg/kg) of NTB