隔区注射AVP和AVP抗血清对家兔温敏神经元放电的影响

THE EFFECT OF MICROINJECTION OF AVP AND AVP-ANTISERUM INTO SEPTAL AREA ON DISCHARGE ACTIVITY OF TEMPERATURE-SENSITIVE NEURONS IN PO-AH OF RABBITS

精氨酸加压素（ＡＶＰ）可能是一种内源性退热剂，其抗热作用的最敏感点位于大脑边缘系统的隔区。为了研究ＡＶＰ抗热作用的机理，本文观察了隔区注射ＡＶＰ和ＡＶＰ抗血清对家兔视前区－下丘脑前部（ＰＯ－ＡＨ）温度敏感神经元放电活动的影响。实验结果如下：（１）隔区注射ＡＶＰ能使ＰＯ－ＡＨ热敏神经元放电明显增加，冷敏神经元放电明显减少；而隔区注射人工脑脊液（ＡＣＳＦ）对热敏神经元和冷敏神经元的放电均无明显影响。（２）隔区注射ＡＶＰ抗血清后，ＰＯ－ＡＨ热敏神经元和冷敏神经元的放电活动则出现了与往隔区注射ＡＶＰ时相反的结果。（３）隔区注射ＡＶＰ能提高ＰＯ－ＡＨ热敏神经元的温度敏感性和降低冷敏神经元的温度敏感性，而隔区注射ＡＶＰ抗血清后则能降低热敏神经元的温度敏感性和提高冷敏神经元的温度敏感性。实验结果表明，ＡＶＰ的退热作用可能是通过兴奋ＰＯ－ＡＨ的热敏神经元和抑制冷敏神经元的活动，而致体温降低。

Arginine vasopress in(AVP)has been shown to have signicant effects on thermoregulation.AVP-sensitive locus is located in the septul area of the limbic system.Thepresent experiments were undertaken to investigate the effect of microinjecting AVPand AVP-antiserum into the septul area on the firing activity of temperature-sensitiveneurons in preoptic-anterior hypothalams(PO-AH)of rabbit.The results were as follows:(1) The firing rate of PO-AH warm-sensitive and cold-sensitive neurons were respectively increased and decreased by injection of AVP while that of temperature-insensitive neurons was unaffected.(2)Injection of AVP-antiserum decreased the firingrate of PO-AH warm-sensitive neurons but increased the firing rate of cold-sensitiveneurons. (3) Injection of AVP increased the thermosensitivity of PO-AH warm-sensitive neurons and decreased the thermosensitivity of cold-sensitive neurons.The modulation action of AVP on PO-AH temperature-sensitive neurons was discussed.