不同等级环境对大、小鼠及其应用的影响

目的了解不同等级环境（屏障环境和普通环境）对实验大小鼠的一般生理表现和抗应激能力以及对药物反应的影响，初步判定严格的微生物控制是否影响实验动物的人类模型作用。方法将40只SPF级Wistar大鼠和200只SPF级BALB／c小鼠分别饲养于屏障环境和普通环境内，通过以下实验对比观察不同等级环境对实验大、小鼠及其应用的影响：每周测量动物的体重增长情况；饲养35d后，测定大鼠15项血液学指标、14项血液生化指标和9个脏器的相对重量；以抗缺氧实验和游泳实验判断对小鼠体质和抗应激能力的影响；以5．氟尿嘧啶急性毒性实验和戊巴比妥钠麻醉实验测试其对药物作用的异同。结果在5周观察期内，屏障环境饲养小鼠和大鼠的体重增长均明显快于普通环境的对照动物（P〈0．05）；普通环境饲养大鼠的血液RBC、WBC、PCT、PLT、GOT、GGT、GPT、CK、TB值高于屏障环境大鼠（P〈0．05），而CHO、LDL-C和HDL-C值低于屏障环境大鼠（P〈0．05）；不同微生物环境条件饲养小鼠的游泳耐力和抗缺氧实验结果接近，但是屏障环境组动物所获数据的变异较小；不同等级环境条件饲养小鼠的戊巴比妥钠麻醉反应和5-氟尿嘧啶中毒反应相似，而屏障环境组动物的麻醉维持时间较短，LD50较低，95％可信限狭窄。结论饲养于屏障环境和普通环境的实验大、小鼠在一般生理表现上出现部分差异，动物的抗应激能力和对药物的反应未发生显著变化；在屏障环境条件中，动物的药物反应更敏感、所获数据更稳定，因此，初步认为严格微生物控制条件下的SPF级动物可以作为生活在自然环境中的人类的模型动物。

Effect of Different Grade Environment on Mice and Rats

Objective To find out if strict microorganism controlled SPF animals are suitable as models of human being living in natural environment. Method 40 SPF Wistar rats and 200 BALB/c mice were assigned into two groups respectively. Group 1 was housed in barrier system, while group 2 was kept in open system. The body weight of rats and mice were measured weekly. After having been kept in the experimental environment for 35 days, 14 hematology and 15 serum chemistry parameters were analyzed and 9 organ weights were measured in rats. Anoxic resistance test and swimming test were conducted in mice. Acute toxicity test of 5-fluorouracil and pentobarbital sodium anaesthesia test were also carried out in mice. Results Rats and mice housed in barrier systems grew faster than that in open systems （ P 〈 0.05）. The values of RBC, WBC, PCT, PLT, GOT, GGT, GFT,CK,TB of rats kept in barrier system were lower than that in open system （ P 〈 0.05）, while the values of CHO, LDL-C, HDL-C of rats in barrier system were higher than that in open system （ P 〈0.05）. There was no significant difference of relative organ weights between the two groups. No significant difference was found in anoxic resistance test and swimming test between the mice in the two groups, but the variation of enduring time of mice kept in barrier systems was less comparing with that in the open system. The reaction to pentobarbital sodium anesthesia and 5-fluorouracil toxicity were similar between the two mouse groups when dosed at the same level, but the shorter duration of anesthesia, less LDso and narrower 95 % reliability range were showed in the mice in barrier system. Conclusion There were some differences of biological characteristics of animals kept in barrier system and open system, but the ability to resist stress and the reaction to pentobarbital sodium and 5-fluorouracil were similar. Animals kept in barrier system appeared more ＇ healthy＇ , and were more sensitive and more reliable in experiments. It revealed that the SPF animals