深度血液稀释对大鼠调节性T细胞和组织代谢的影响

Effects of profound hemodilution on regulatory T cells and tissue metabolism of rats

目的探讨深度血液稀释对大鼠渊节性T细胞(Treg)及组织代谢的影响。方法健康雄性SD大鼠,体重350～400 g,戊巴比妥腹腔注射麻醉后,解剖颈总动脉连接L-420E动物测压系统监测血压和心率,并用于放血和进行血气分析;解剖股静脉后留置24G套管针,备采血和输液用;输液用微量注射泵泵入,先输羟乙基淀粉,后输携氧液,羟乙基淀粉与携氧液之比为1:2。当红细胞压积值达目标值(<20%)时,静脉输液停止。分别于稀释前和稀释后即刻取静脉血1mL置于EDTA-K_2抗凝管中送流式细胞仪检测CD_4和CD_(25)。稀释结束后24 h处死动物,取心、肺、肝、肾组织制片,光镜下进行病理学观察。结果3只大鼠被剔除。17只大鼠红细胞压积值达目标值17.41%±1 28%,且全部存活,输液量(32.88±1 65)mL,动物放血量(10.004±2.00)mL,血液稀释所用时间(60.00±10.00)min。血液稀释前后Na^+、K^+、Ca^(2+)浓度及pH、CO_2分压、心率、血压变化无统计学意义,血液稀释后CD_4^+CD_(25)^+、氧分压高于稀释前(P<0.01),心、肺、肝、肾等组织无缺血、缺氧及水肿改变。结论应用携氧液行深度血液稀释,可使大鼠外周血中Treg细胞及血氧分压明显升高,血流动力学稳定,可改善组织氧供给。

Objective To study the effects of profound hemodilution with oxygen-carrying liquid on regulatory T cells and tissue metabolism of rats. Methods Twenty male adult SD rats weighting 350-400 g were used. The animals were anesthetized with intraperitoneal pentobarbital. Arteria carotis communis were cannulated for heart rate and blood pressure monitoring and hemospasia, the arterial blood-gas was detected too, femoral vein was dissected and 24G venous cannula was detained for intravenous infusion. Blood was withdrawn from artery and simultaneously replaced by intravenous infusion of 6% hydroxyethyl starch and oxygen-carrying liquid by small volume injection pump until hematocrit arrived at objective value（〈20%）. Blood samples were taken before hemodilution and at the end of hemodilution for determination of regulatory T cells by flow cytometry and analysis of blood-gas. After 24 h, the animals were killed and the heart, lung, liver and kidney of animals were gained to put into the container with formalin, the materials were used for pathological sectioning. Results 17 rats survived and hematocrit reached objective value 17.41%±1.28%. Hematocrit was significantly attenuated（P 〈0.01）. CD4^＋CD25^＋ and oxygen partial pressure were significantly increased（P 〈0.01）. The pathological section displayed that the tissues were non-anoxyaemia and non-edema. Conclusion The regulatory T cells of rats may be significantly increased through profound homedilution, and the oxygen partial pressure of rats may be significantly improved by oxygen-carrying liquid.