Abstract: Effects of chronic hypoxia on liver of Ochotona curzoniae and rats have been carried out by simulated altitude (5000m,Po₂ 84mmHg, O₂ 11%) in hypobaric presure chamber for 15 days, and compared with those at 2300 m of altitude (120mmHg of Po₂, O₂ 16%).In fourth filial generation of rats removed from the lowland to Xining (2300 m of altitude)the levels of content of glycogen,lipid and protein mar- kedly decreased from 753 ± 34.9, 869±23.2 and 1113 ± 11.3 to 384±25.8,606 ±23.8 and 814 ± 8.1 mg/whole liver respectively(P<0.001)during exposuring to 5000 m altitude for 15 days, while the activities of lysosomal enzymes, acid phcsphatase and aryl sulpbatase, enharced significantly (P<0.001), whereas SGPT and SGOT kept unchanged. The biochemical changes were supported by hepatic morphological evidence that hypoxia led to cloudy swelling and ballooning of cells and parenchymal cell necrosis. However none of changes had been observed in these indexes mentioned above in native mammal pika (O.curzoniae) at the same experimental conditions.The data, therefore, suggested that obvious different mechanism of adaptation to hypoxia chronically in hepatic metabolisms and enzymes related to hepatic function and damage of liver cells necrosis existed between rats and O. curzoniae. The perfect mechanisms uniformed structure and functions of acclimatization to altitude in liver of O. curzoniae were formed by long term of evolution at cellular and molecular level. The model of O. curzoniae would serve us for searching the principle of adaptation based on molecular biology to hypoxia. Much attention must be paid in terms of effects of hy-poxic hypoxia either acutely or chronically upon liver clinically.

Key words: Pika, Ochotona curzoniae, Rat, Hypoxia, Liver metabolism, Aminotransferase, Lysosomal enzymes

摘要： 我们曾经发现,移入高原的实验大鼠子一代和高原鼠兔(Ochotona curzoniae)对高原低气压低氧有完全不同的适应能力和适应机理(杜继曾等,1982)。我们还观察到,在24小时急性高原低氧时,由低地移入2300米高原的大鼠后裔在5000米和8000米的高度上,出现了以转氨酶、肝溶酶体酸性磷酸酶活力升高、肝糖原和蛋白质含量下降的肝脏代谢异常和肝脏病理变化,而高原鼠兔只是在8000米高度时,才始出现部分指标的轻度变异(杜继曾等,1982),从而揭示了高原鼠兔的肝细胞代谢在细胞水平上对低氧的适应机制优越于移入高原的实验大鼠后代。慢性低氧又如何作用于大鼠和高原鼠兔的肝脏代谢?迄今尚无人研究。因此对这一作用规律的认识和阐明,在环境适应生理学领域、人类高原活动和畜牧业生产上都是十分重要的。

关键词: 高原鼠兔, 大鼠, 低氧, 肝代谢, 转氨酶, 溶酶体酶