呼吸兴奋剂、吗啡及安定等药物影响呼吸中枢的低氧反应

A STUDY OF HYPOXIC EFFECTS ON RESPIRATORY NEURONS AND THE RESPONSE TO RESPIRATORY STIMULANTS, MORPHINE AND DIAZEPAM IN RABBITS

以家兔自身低氧血灌注其低位脑干引起呼吸抑制为实验模型,探讨临床上常用的6种呼吸兴奋剂以及吗啡、安定等药物对呼吸中枢低氧反应的影响。结果表明:尼可刹米、美解眠、氨茶碱、吗乙苯吡酮、洛贝林和阿米屈仑除了提高通气量外,都还能明显提高呼吸中枢低氧耐受力,但两者之间无平行关系。吗乙苯吡酮和阿米屈仑还能使动脉血中P_o_2增高,P_(?o)_2降低。吗啡和安定可显著降低呼吸中枢低氧耐受力。

Using the animal model reported in our previous paper, hypoxic effects on-ventilation were elicited by perfusion of the hypoxio blood to the lower brain stem in rabbits. Six respiratory stimulants as well as morphine and diazepam were investigated to ascertain whether their actions could lessen or enhance the hypoxio effecs on ventilation. All drugs were administered intravenously. The results were: (1) Nikethamide, megimide, aminophylline, dosapram, lobelin and almitrine could markedly increasea VT and f of spontaneous respiration, besides, doxapram and almitrine increased the PaO2 and decreased PaCO2 significantly. In addition, these respiratory stimulants can improve tolerance of the respiratory neuron to hypoxia; (2) morphine, in addition to its depressant effect on both VT and f decreased the central hypoxio tolerance markedly, diazepam was shown to have depression on ventilation. In this study, diazepam did not decrease either VT or f, but did decrease PaO2 (ca. 11%) and increase PaCO2(ca. 17%) significantly, it also decreased central hypoxic tolerance. These, results provide experimental basis for further studies.