Effects Of TCST On The Expression Of NF-κB After Focal Ischemic Damage In Rats

Background and objective: As the development of Chinese economic and the improvement of living standards, the incidence of ischemic cerebrovascular disease has increased annually, has become the leading cause of death in Chinese population. It has became a serious threat to life and health of our people, and brought about many problems to patients, families and the society. Therefore, it is necessary to give treatment timely and effectively in the early stage of the disease. Given treatment timely and effectively has close relationship in reducing mortality and improving the prognosis of the disease.It has also been a hot issue. to domestic and foreign scholarsIschemic cerebrovascular disease is caused by various reasons: the disorder of blood supply to the brain vascular lead to hypoxia and necrosis occurred irreversible damage of the involved cerebral ischemia, and the corresponding signs and symptoms caused by neurological deficits. Clinical treatment methods are commonly used ,such as thrombolytic drugs, anticoagulation and interventional vascular expansion and so on. These methods are after long-term clinical application, has been confirmed that there is some scientific and use, but there are limitations. Therefore, domestic and foreign researchers have been exploring the onset of ischemic cerebrovascular disease a new treatment.Stellate ganglion block (SGB) is to inject of local anesthetic in the loose connective tissue nearby the stellate ganglion of the neck to block disposable head, face, neck, upper limbs and upper chest sympathetic approach. This method of sympathetic blockade in these areas inhibit the control of cardiovascular exercise, glandular secretion, muscle tension, bronchial contraction and the conduction of pain nerve fibers. Thus, stellate ganglion block can correct circulation disturbance, hyperalgesia, abnormal sweating and other changes of the organs, which are caused by the hyperexcitability of sympathetic nerve. In recent years, this method was multi used in clinical treatment of ischemic cerebrovascular disease. It can improve the blood vessel spasm or dilated abnormal activities notably, and make the vessel stable. It also can reduce the edema of the vessel, have the anti-inflammatory effect, block the pain transmission of the sympathetic nerve. The specific mechanisms of this method is also reported at internal and abroad, and it mainly focus on increasing the flow speed of brain blood faster, reducing stress reaction, regulating the immune system and so on.The purpose of this study is to research the activation of nuclear factor-kappa B (NF-κB) and the regularity of the activation after focal ischemic damage in rats, and investigate the effect of transection of cervical sympathetic trunk (TCST) that can simulate the way human SGB to the levels of NF-κB activation in focal cerebral ischemia in rats brain.Methods: In this study, male Wistar rats were selected randomly and divided into 3 groups: sham operation group (S group), MCAO model group (M group), TCST treatment group (T group). According the embolizated time the rats were divided into 4 different subgroups randomly.There were 6 hours, 12 hours, 24 hours, 48 hours.The animals of S group as a sham control group; the animals of M group as MCAO model; The rats of T group break away from the ipsilateral sympathetic trunk in the MCAO model produced at same time. Detected the activation of NF-κB in the hippocampus of rat brain after middle cerebral artery occlusion time course point M group and T group by immunohistochemistry Also, observed the general state of animals and brain morphological change of the rats which the cervical sympathetic trunk off.Results: The results showed that the general condition and neurological deficit score: S awake rats after general anesthesia in good condition, M rats, poor general state, T group, though not of the general state of S rats, but better than the M group in large good general state of rats. T group simultaneous ipsilateral ptosis, eye fission small, miosis and other typical signs of Horner's syndrome; S group showed no neurological deficit or signs of Horner's syndrome. M group and T group rats after consciousness from anesthetizing were showing neurological impairment. M group compared with the S group, p <0.01, significant difference between the two groups, M group of neurological deficit scores were significantly higher than the S group; T group compared with the M group, p> 0.05, between the two groups of nerve impairment scores showed no difference. under the light microscope observe the microtome section of the rat brain which dyeing by hematoxylin-eosin staining, the infarcted area locate in the caudate nucleus, putamen, anterior and lateral hypothalamus, hippocampus CA1, CA2, CA3 area mostly. The changes of hippocampal CA1 neurons showed: Neurons of S group are more closely arranged neatly, the cells complete; under the high-power lens, the nuclei are large and round, and the nucleoli are prominent. The neurons of S groups subgroups are similar. The neurons in 6h subgroups of M group became swelling. No significant change in the number of neurons. after cerebral ischemia 24h, the number of neurons began to decrease, and the cell became degenerating. The cells of T group have been changes in ischemic pathology in the corresponding point in time there, but comparing with the M group, the pathological manifestations is lighter. Observed the expression of NF-κB under light microscope by immunohistochemical staining, the cytoplasm of cells showed positive, the nucleus stained yellow; negative cells showed only cytoplasmic stained yellow. The expression of NF-κB began to increase in the nuclear after 6 hours of cerebral ischemia, the expression increase to peak after 24 hours, then gradually reduced. The nuclear expression of NF-κB in the T group was significantly lower than the M group.Conclusions: The experimental results show that the infarct region mainly in the caudate nucleus, putamen, anterior and lateral hypothalamus, hippocampus CA1, CA2, CA3 area. The activation of NF-κB enhance after focal cerebral ischemia, and reach the peak after 24 hours. According analysis and comparison the result between the TCST group and the MCAO group, we found that transection of cervical sympathetic trunk of ischemic stroke can significantly improve the general state of animals, improve the pathological ischemic injury, decrease activation of NF-κB and reduce the stress on the brain ischemia and tissue injury, protect the brain.