电刺激中央中核对猫丘脑后核群内脏大神经诱发单位放电的影响

EFFECTS OF ELECTRICALLY STIMULATING CENTROMEDIAN NUCLEUS ON NEURON DISCHARGES IN POSTERIOR GROUP OF THALAMIC NUCLEI EVOKED BY EXCITATION OF GREATER SPLANCHNIC NERVE IN DAT

用细胞外微电极记录方法和条件检验刺激技术,研究电刺激中央中核对猫丘脑后核群内脏大神经诱发单位放电的影响。中央中核对该诱发单位放电主要表现为抑制作用,少数为易化作用抑制与易化双重作用或无作用。中央中核的抑制作用可分为即时抑制、迟延抑制和持续抑制三种形式。纳洛酮可拮抗中央中核的即时抑制和持续抑制作用。

As an index of visceral pain, the discharges of The neurons in the post-erior group of thalamic nuclei (PO), evoked by stimulating greater splanchnicnerve (SPL) in 26 cats were investigated extracellularly. The effects of cent-romedian nucleus (CM) on the unit discharges were also studied with test-conditioning stimulation techniques. Stimulating CM (conditioning stimulus) electrically, the neuron dischar-ges in PO, caused by excitation of SPL (test stimulus) were mainly depressed.In 63 neurons, unit discharges of 59 (93.7%) were affected. Among them,unit discharges of 50 neurons (79.4%) were inhibited, 4 neuron (6.3%)activities were excited and 5 (8%) had both inhibition and excitation at thesame time respectively. Unit discharges of 4 (6.3%) were unaffected. Theinhibition of neuron discharges in PO produced by stimulating CM can beclassified in three kinds: prompt inhibition, delayed one and continued one.The prompt and continued one were antagonized by naloxone. It was sugges-ted that CM played an important role in analgesia of visceral pain.