关键词: 高原鼠兔, 肺泡Ⅱ型细胞, 表面活性物质, 超微结构

Abstract: Effects of hypoxia on ultrastructure of type Ⅱ epithelial cell and pulmonary surfac-tant,system in Ochotona curzoniae, altitude-migrated rats (the fourth filial generation of Wistar rats from the lowland to Xining, then before the experiment migrated to 3300m), and altitude-brought Wistar rats (from the lowland brought to 3300m)have been carried out, and the lowland Wistar rats were as control group.The results showed the percentage of lung weight of O. curzoniae was not as heavy as in altitude-migrated rats (P>0.05) and altitude-brought rats (P<0.001), but similar to that of the lowland rats.Their lung tissus were observed with transmission electron microscope and scanning electron microscope. The results showed that the microvilli of type Ⅱ epithelial cells decreased, mitochondria degenerated and swelled, the lamellar bodies evacuated and the synthesis markedly reduced in altitude- brought rats, while the ultrastructure of those cells of the lowland rats was normal. However, none of changes had been observed in these indexes mentioned above in native mammal pika(O. curzoniae) at the same experimental conditions. The ultrastructure of altitude-migrated rats varied between O.cur-zoniae and altitude-brought rats.

Key words: Plateau pika, Ochotona curzoniae, Type Ⅱ alveclar cells, Surfactant system, Ultrastructure