Gainer J L, Lipa M J, Ficenec M C
Department of Chemical Engineering, University of Virginia, Charlottesville 22903-2442, USA.
Lab Anim Sci. 1995 Apr;45(2):169-72.
Rats are commonly used as models of hemorrhagic shock. Both constant-pressure and constant-volume protocols have been used, although the latter is considered by some to be a better model of human shock. However, differences in survival have been reported when the same experiment is done by different investigators. Changes in oxygen consumption have been reported to correlate with mortality after shock, and these changes may be implicated in the variability seen in different experimental studies. Using the constant-volume model, in which a given percentage of the animal's estimated blood volume is withdrawn, we have determined oxygen consumption rates before and after hemorrhage in Sprague Dawley rats. Our results indicate that specific oxygen consumption rates decrease once rats reach a certain weight, but removing a given percentage of blood reduces the rate by a constant amount regardless of the weight of the animal. In addition, there appears to be a "critical" level of oxygen consumption needed for survival. Thus use of a constant-volume protocol could result in survival for smaller but not larger rats. It is suggested that rat weights must be the same to compare results from different investigators.
大鼠通常被用作失血性休克的模型。恒定压力和恒定容量方案都已被采用，尽管有些人认为后者是更接近人类休克的模型。然而，不同研究者进行相同实验时，报告的存活率存在差异。据报道，休克后氧耗的变化与死亡率相关，这些变化可能与不同实验研究中观察到的变异性有关。使用恒定容量模型，即抽取动物估计血容量的特定百分比，我们测定了斯普拉格·道利大鼠出血前后的氧耗率。我们的结果表明，大鼠一旦达到一定体重，单位氧耗率就会下降，但无论动物体重如何，抽取给定百分比的血液会使氧耗率以恒定幅度降低。此外，似乎存在一个生存所需的“临界”氧耗水平。因此，使用恒定容量方案可能会使较小的大鼠存活，但较大的大鼠则不然。建议不同研究者比较结果时，大鼠体重必须相同。
