Adaptation to high-altitude

鼠兔(鼠兔属Ochotona)是我国特有的高海拔物种，分布于海拔10-6,100米的低海拔和高海拔地区。1986年8月，我们在青海中国地区捕获了海拔2.300m(n=13)、3300m(n=15)和4460m(n=14)的鼠兔，并对捕获点的血液动力学参数进行了测定。1987年8月，我们使用了低空Pikas(海拔650米。N=10)，1974年从法国进口到日本，由一家日本动物公司饲养。测定了高原鼠兔的肺动脉压(P&lt；@2PA&lt；@D2)、右室重量比(RVW/LVW)、红细胞数(RBC)、平均红细胞体积(MCV)、红细胞压积(HT)、全血粘度、红细胞变形性和氧耗(Vo&lt；@D22@&Gt；D2)。并与大鼠进行比较。结果表明：1)鼠兔的P&lt；PA&Gt；、RVW/LVW和Ht值均显著低于各海拔范围的大鼠；2)鼠兔和大鼠的P&lt；PA&Gt；、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分别小于大鼠。鼠兔的RVW/LVW、Ht、MCV、血液粘度和VO2均低于大鼠。虽然在红细胞和红细胞变形性方面没有发现差异，但差异有统计学意义。结论：低海拔梭子鱼也显示出一些高原适应的迹象。

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.