局部冷冻对血管及机体合成一氧化氮的影响

The Effect Of Local Freezing On Synthesis Of Nitric Oxide From Blood Vessel And Host

目的:本实验通过对在体家兔动脉及心脏局部冷冻,观察冷冻对血管合成一氧化氮功能的影响,以及机体对冷冻的全身性反应的有关征象。方法:以家兔作为实验对象,随机分成对照组和冷冻组,以Ignarro和Green法测定血管壁的NO_2^-含量,以Shechter法测定NO_2^-浓度,在实验中分别测定冷冻前后血管壁和血液中心NO_2^-浓度。结果:①主动脉及股动脉壁冷冻10秒复温后随时间的延长动脉管壁NO_2^-含量逐渐升高。②对主动脉管壁冷冻2分钟后可见主动脉管壁NO_2^-含量明显下降。③对主动脉壁冷冻10秒钟后,血液中的NO_2^-含量未见明显变化。①对心脏心外膜冷冻10秒钟后血液中NO_2^-含量未见明显变化。结论:血管壁的冷冻对血管合成一氧化氮(NO)的功能影响较大,当冷冻时间较短时,血管壁合成NO的量随时间延长而增多。但是,随首冷冻时间增加,血管壁合成NO的量减少,由此可造成不良的后果。

Objective: To study the effect of freezing on the synthesis of nitric oxide from blood vessel and the signs of systemic reaction of host to freezing. Methods: The rabbits were divided into control and experimental group according to randomnization. Freezing was carried out at blood vessel and heart surface. NO concentration was measured with Ignarro Green and Shechter method. Results: (1)NO concentration increased in artery wall as freezing at aorta and femoral wall lasted for 10 seconds but decreased as freezing time prolonged to 2 minutes at aorta wall. (2)NO significant change of NO concentration in blood occured as freezing at aorta wall and heart surface lasted for 10 seconds. Conclusions:The freezing on the blood vessel effects synthesis of NO from the vessel wall significantly. When the freezing is limited in very short time, the freezing can stimulate the synthesis of NO in vessel wall and the synthesis is enhanced with the prolongation of time,but when the freezing time i.s prolonged(2 minutes in our experiment). the synthesis of NO is inhibited significantly, which may induce severe adverse effect.