不同减压负荷对家兔血清丙二醛和超氧化物歧化酶的影响

目的 通过观察不同速率的快速加减压对家兔血清超氧化物歧化酶(superoxide dismutase,SOD)和丙二醛(malondiadehyde,MDA)的影响,探索快速上浮脱险压力暴露机体氧化损伤负荷的变化规律.方法 3批共26只成年新西兰兔,以2t/4指数速率加压至150 m,分别停留80 s(10只)、75 s(8只)和58 s(8只),随后以25 s匀速减至常压.观察暴露前后家兔的行为改变,取动物暴露前和出舱后15 min内血清测定MDA和SOD值.结果 动物出舱后行为均未见异常.各组暴露后血清MDA浓度较暴露前高,但差异均无统计学意义(P>0.05).80 s组家兔血清SOD暴露前后差值与75 s、58 s组暴露前后差值相比显著降低,差异均有统计学意义(P<0.01).血清SOD含量变化程度与SPdt整个高压暴露时间内脱险深度与时间乘积倍数的总和存在相关性,停留时间与SPdt、暴露前后差值均存在相关性(分别r=0.920、0.555、0.572,P<0.01).结论 此次快速上浮脱险模型没有造成家兔显著减压病表现,但引起机体抗氧化能力降低,这种降低与高压停留时间和SPdt值相关.

Effects of different decompression load on the changes of serum malondiadehyde and superoxide dismutase in rabbits

Objective To explore the change pattern of oxidative lesion induced by fast buoyancy escape pressure exposure through observing the effects of fast compression and decompression at different rates on the serum superoxide dismutase ( SOD) and malondiadehyde(MDA) in rabbits.Methods Three batches of 26 male adult New Zealand rabbits were compressed to a pressure of 1.5 MPa at an exponential rate of 2t/4 with compressed air, and stayed at the said pressure for respectively 80, 75 and 58 seconds, then, the animals were decompressed to atmospheric pressure at linear speed .Changes in the animal behavior were closely observed both before and after pressure exposure , and serum samples of the animals before exposure and 15 minutes after exposure they were brought out of the chamber were collected to detect the levels of SOD and MDA .Results No abnormal behavior could be observed in all the animals, when they were brought out of the chamber .Following exposure , serum MDA levels of all the 3 groups were obviously higher than those before exposure , but no statistical significance could be noted , when comparisons were made between pre and post ex-posure(P>0.05).The variation in the serum SOD level of the 80 s group both before and after exposure was significantly lower than those of the 75s and 58s groups, and statistical significance could be seen when comparisons were made between them (P<0.01).The variation of serum SOD was closely correlated with SPdt , and the duration of stay at pressure was correlated with SPdt and the variations before and after exposure(r=0.920, 0.555, 0.572, P<0.01).Conclusion The fast buoyancy escape pressure exposure did not in-duce significant manifestations of decompression sickness in rabbits , but resulted in the decrease of anti-oxidative capacity , which was closely associated with the duration of stay at pressure and the SPdt value .