【作者】 董玮；

【导师】 唐成林；

【作者基本信息】 吉林大学 ， 外科学， 2005， 硕士

【摘要】 目的:探讨电针对脊髓损伤后一氧化氮合酶（NOS）基因表达影响,寻找继发性脊髓损伤的发病机制,为脊髓损伤的治疗奠定基础。 方法:采用对照组的方式,将30只SD大鼠随机分为电针组、模型组、正常对照组。其中电针组与模型组采用改良的Allen’s垂击法致大鼠脊髓(T₁₀)中度损伤,电针组于损伤2小时后立即进行电针治疗,于术后1、4、24、48小时处死动物,取伤段脊髓用RT-PCR法测定各型NOS mRNA的表达。 结果:通过对30只大鼠nNOS mRNA和iNOS mRNA的表达的研究发现,电针组均较模型组减少。 结论:电针可不同程度的降低NOS mRNA的表达,降低NOS活性。电针早期治疗可能通过降低一氧化氮的形成减轻脊髓继发损伤而起到对神经的保护作用。更多还原

【Abstract】 Spinal cord injury(SCI) is a common injury in the traumatology. SCI often causes quadriplegia and paraplegia, influences the people’s life quality, and severely damages the human health. It is a great problem for the medical staffs to decrease the secondary SCI, accelerate the regeneration of spinal nerves, and regain the nervous function. The electric stimulation therapy has a long history, and gained very good effect. This test use the rat model, and the reverse transcription (RT) method to measure the expression of all kinds of nitricoxide synthase(NOS) mRNA.All the 30 rats are male, weighs between 210-260gs, randomly divided into 3 groups: electric stimulation(ES) group, model group, and control group. Electric stimulation and model group use the modified Allen’s vertical hammer method with the strength of 5g×10cm to achieve moderate SCI(T10), injury diameter 2.5mm. After established the models, give the ESgroup pulse electric stimulation after 2hs, 30 minutes each time, one time per day. No treat to the model and control group. All the animals was put to death in strict aseptic condition when 1, 4, 24, and 48 hours posttrauma, cut out 1.5cm long spinal cord, making into homogenate, and then measure the expression of the NOS mRNA with RT-PCR. The results shows that there is expression of nNOS mRNA in normal condition, and the expression levels were all raised at 1,4, and 24 hours post SCI, the peak was at 1 hour, and decreased after that, returned to normal at 48 hours post SCI. The expression of all the ES groups except the 48h group was statistically less than that of the model groups. There is no statistically difference between the 24h and 48h ES groups and the control groups. There is no iNOS mRNA expression in 1 and 4 h post SCI and control groups, only little expression in 24h post SCI group, and increased expression in 48h post SCI group. There is no iNOS mRNA expression in 24h ES group, and the expression in 48h group was sharply decreased than that of the control group. There is no obvious influence of electric stimulation to theexpression of eNOS mRNA.NO is an unstable highly diffused free radical, and the biological function was mainly brought about by many chemical reactions, widely influencing the information conducting processes, energy metabolism and DNA synthesis. In physical condition, NO acts as the vasodilator, increasing the spinal cord blood flows, but the expression of NOS post SCI and the secondary elevation of NO take part in the pathological process of secondary SCI, and induce the elevation of glutamic acid and aspartic acid, aggravating the secondary SCI.The formation of NO in central nervous system is catalyzed by NOS. NOS is the only restriction enzyme. Since the half life of that was too short, NO was not easy to research directly, so it is usually to measure the activity of NOS to reflect the synthesis of NO. There are 2 kinds of NOS in central nervous system, cNOS and iNOS. The activity of cNOS depends on the Ca2+ and calcium modulating albumin (CMA), and reacts to the environmental stimulation rapidly, generating large amount of NO in short time, that may play an importantrole in the early stage after SCI. The function of cNOS in SCI is not clear. The cNOS includes nerve NOS (nNOS) and endothelium NOS (eNOS). There are great difference of the function of both of them in tissue injury. nNOS was considered to induce the neurotoxicity in early stage post CNS injury.Electric stimulation is a kind of therapy of SCI, and the mechanism is not clear. The mechanism of pulse stimulation to treat SCI may be: a, pulse stimulation lead to effective polarization of neurons, and reach the same effect as that of the direct current. Meanwhile, since the nerve fibers gain active moves, increase the enzyme activity of neurons, the transportation of axons, and the metabolism, and they are good to regeneration, b, the pulse stimulation can increase the growth and regeneration of nerve fibers post SCI, and change the function state of neurons, c, it can wake up the shock or dormant spinal cord post SCI.This test results show that: the early electric stimulation therapy can decrease the expression of nNOS mRNA, iNOS mRNA, the activity of NOS, and the generation of NO, but no更多还原