Maskrey M, Hinrichsen C F
Department of Physiology, University of Tasmania at Hobart, Australia.
Pflugers Arch. 1994 Mar;426(5):371-7. doi: 10.1007/BF00388299.
Urethane-anaesthetised rats were exposed to hypoxia (7% O2 in N2) for 5 min periods while body core temperature (Tbc) was maintained within the normal range (37-38 degrees C) using an abdominal heat exchanger. Animals were exposed to hypoxia and after placement of electrolytic lesions in either the anterior (n = 6) or posterior hypothalamus (n = 6). Neither lesion altered respiration while rats breathed air at either Tbc. At normal Tbc, rats responded to hypoxia with increased ventilation throughout the exposure period. This response was unchanged by lesions in either location. At reduced Tbc rats responded to hypoxia with an initial increase in ventilation followed by depression to below air-breathing levels. This depressive response was unchanged after anterior hypothalamic lesions but eliminated after posterior hypothalamic lesions. It is concluded that neurons either originating in the posterior hypothalamus, or passing through it, play a role in the interaction between cold and hypoxia which leads to inhibition of respiration.
给氨基甲酸乙酯麻醉的大鼠暴露于低氧环境（氮气中7%氧气）5分钟，同时使用腹部热交换器将体核温度（Tbc）维持在正常范围（37 - 38摄氏度）。将动物暴露于低氧环境，并在前下丘脑（n = 6）或后下丘脑（n = 6）进行电解损伤。在任一部位损伤后，当大鼠在正常Tbc下呼吸空气时，呼吸均未改变。在正常Tbc时，大鼠在整个暴露期对低氧的反应是通气增加。该反应在任一部位损伤后均未改变。在降低的Tbc时，大鼠对低氧的反应是通气先增加，随后降至低于呼吸空气时的水平。前下丘脑损伤后这种抑制反应未改变，但后下丘脑损伤后消除。得出的结论是，要么起源于后下丘脑，要么穿过它的神经元，在寒冷与低氧之间的相互作用中起作用，这种相互作用导致呼吸抑制。
