Hypoxic poikilothermia in rats.
Hypoxic poikilothermia in rats.
复制标题
大鼠缺氧低温。
DOI：
10.1152/jappl.1969.27.5.583
复制
发表时间：
1969
影响因子：
3.3
通讯作者：
T. Rao
中科院分区：
文献类型：
--
作者：
B. Bhatia;S. George;T. Rao
方法在夏季进行的第一系列实验中，在减压室内的地面水平、模拟海拔10,000、15,000、20,000、30,000和32,500英尺以及干球温度10、15、20、25和30℃下记录大鼠的直肠温度。在冬季进行的第二系列实验中，记录了大鼠在地面、模拟高度10,000、15,000、20,000和25,000英尺以及干球温度15、20、25、30和35℃下的直肠温度。燃烧室配备了加热和冷却装置，通过恒温器控制将室内温度保持在所需的水平。室内湿度约为50%。气室一端附近的受控通风口允许新鲜空气以3.5英尺/分钟的速度进入气室。从放置动物的气室另一端附近记录的空气温度变化不超过RT 1℃。由于通风率高，空气运动对动物的降温作用被发现是可以忽略不计的。实验动物为白色近交系雄性大鼠，饲养于本研究所的动物舍内。他们出生在14-25周，体重在150-200克之间，在新鲜准备和平衡的饮食中随意喂养。它们在冬季保持在室温24℃，在夏季保持在28&2℃。在第一个研究中使用了六组大鼠，每组六只大鼠，在第二个研究中使用了五组大鼠。用热电偶和灵敏电流计测量非麻醉大鼠的直肠温度。结果在不同的模拟海拔高度和气温下，直肠平均温度及其标准差如表1所示。直肠温度随大气压力的降低而逐渐下降。有趣的是，即使在30摄氏度的气温下，这种趋势也很明显，这非常接近动物的中性温度。
METHODSIn the first series of experiments carried out during the summer months, rectal temperatures of rats were recorded at ground level and at simulated altitudes of 10,000, 15,000, 20,000, 25,000, 30,000, and 32,500 ft and at drybulb temperatures of 10, 15, 20, 25, and 30 C within the decompression chamber. In the second series of experiments carried out during the winter months, rectal temperatures of rats were recorded at ground level and at simulated altitudes of 10,000, 15,000, 20,000, and 25,000 ft and at dry-bulb temperatures of 15, 20, 25, 30, and 35 C. The animals were subjected to simulated altitudes by placing them in a cylindrical decompression chamber with a capacity of 2 ft3. The chamber was provided with heating and cooling arrangements, which maintained the’temperature within the chamber at desired level by means of a thermostat control. The humidity within the chamber was about 50%. A controlled vent near one end of the chamber allowed fresh air at the rate of 3.5 ft3/min to enter the chamber., The temperature of the air as recorded from near the other end of the chamber, where the animal was placed, did not vary more than rt 1 C. The cooling effect of air motion on the animal owing to the high ventilation rate was found to be negligible. The animals used were white, inbred male rats which were raised in the animal house of this Institute. They were 14-25 weeks old, weighed between 150-200 g, and were fed ad libitum on a freshly prepared and balanced diet. They were maintained at a room temperature of 24 rt 2 C in winter and 28 & 2 C in summer. Six groups of rats, each of six rats, were used in the first study, and five groups of rats, in the second study. The rectal temperatures were measured by use of thermocouples in unanesthetized rats, inserted into the rectum to a depth of 7 cm, and a sensitive galvanometer.RESULTS The mean steady-state rectal temperatures, together with their standard deviations at different simulated altitudes and air temperatures, are given in Table 1. There is a progressive fall in the rectal temperatures with decline in the atmospheric pressure. It is interesting to note that this trend is evident even at an air temperature of 30 C, which is very close to the neutral temperature of the animals.