Adaptation to high-altitude

鼠兔属（Ochotona）是一种古生物学证明极其原始的高海拔原生种，分布广泛，从低海拔到高海拔（海拔10- 6100m）。1986年8月，我们在中国青海地区海拔2300 m（n=13）、3300 m（n=15）和4460 m（n=14）处捕获鼠兔，并测量了捕获地点的一些血流动力学参数。1987年8月，我们使用了1974年从法国进口到日本，由日本动物公司饲养的低空鼠兔（海拔650米n=10）。我们测量了低空鼠兔肺动脉压（P<@2PA<@D2）、右心室重量比（RVW/LVW）作为右心室肥厚的指标、红细胞数量（RBC）、平均细胞体积（MCV）、红细胞压积（HT）、血液粘度、红细胞变形能力和耗氧量（Vo<@D22@>D2）。并与大鼠进行比较。结果表明：1)鼠兔的P_<PA>、RVW/LVW和HT与各海拔高度的大鼠相比均显著降低。2)鼠兔和大鼠的P_<PA>、RVW/LVW和Ht值均随海拔升高而升高，但鼠兔随海拔升高的幅度均小于大鼠。3)与大鼠比较，低海拔鼠兔的P_<PA> RVW/LVW值。鼠兔的Ht、MCV、血黏度、VO_2均低于大鼠。尽管在红细胞和红细胞变形性方面没有发现差异，但差异具有统计学意义。结论：低空钉螺也有一定的高原适应迹象。

Pika (the genus Ochotona), paleontologically proved th be extremely primitive, is one of native high altitude species and the distribution ranged widely from low to high altigudes about 10-6,100m above sea level).In August 1986, we captured the Pikas at Qinghai areas in China, 2.300m(n=13), 3,300m(n=15), and 4,460m(n=14) above sea level and measured some hemodynamic parameters in captured places. In August 1987, we used the low-altitude Pikas (alt 650m. n=10)which had been imported from France to Japan in 1974 and were bred by a Japanese animal company. We measured the pulmonary artery pressure (P<@2PA<@D2), right ventricular witght ratio(RVW/LVW) as an index of the right ventricular hypertrophy, number of red blood cell (RBC), mean cell volume (MCV), hematocrit (HT), blood viscosity, red cell deformability and the oxygen consumption(Vo<@D22@>D2) in the low altitude Pikas. The values were compared with those of rats. The results were as follows:1) The P_<PA>, RVW/LVW and HT in Pika showed significantly low values compared with those of rats in all altitude ranges.2) The P_<PA>, RVW/LVW and Ht values increased with altitudes in both Pika and rat, but the extents of increase with altitude in Pikas was respectively less than that of rats.3) By comparing the low-alltitude Pikas with rats, the values of P_<PA> RVW/LVW.Ht,MCV, blood viscosty, and VO_2 in Pika were shown to be lower than those of rats. The differnces were statistically significant, although no difference was found in RBC and red cell deformability.Conclusion: The low-altitude pikes also indicated some signs of highaltitude adaptation.