降钙素基因相关肽对大鼠全脑缺血再灌注脑组织SOD、MDA和NOS的影响

目的研究降钙素基因相关肽(CGRP)对大鼠全脑缺血再灌注(I/R)脑组织自由基和脂质过氧化反应的影响及神经保护作用的机制。方法45只SD大鼠，随机分为假手术组、对照组、CGRP组。采用四血管阻断方法制备SD大鼠全脑I／R模型，化学比色法测定大脑皮质、海马组织的丙二醛(MDA)含量、超氧化物歧化酶(SOD)和一氧化氮合酶(NOS)活性。结果与假手术组比较，大鼠全脑．I／R后大脑皮质、海马组织MDA含量、NOS活性升高，SOD活性降低。CGRP应用对I／R后MDA含量的升高有明显抑制作用，对SOD和NOS活性变化的作用不显著。结论CGRP对大鼠全脑I／R脑组织自由基损伤有保护作用。

The effects of CGRP on the activities of superoxide dismutase and nitric oxide synthase and the content of malondialdehyde in the rat model of whole cerebral ischemia/reperfusion

Objective To study the effects of calcitonin gene-related peptide (CGRP) on the activities of superoxide dismutase(SOD) and nitric oxide synthase(NOS) and the content of malondialdehyde (MDA) in brain tissue after whole cerebral ischemia/reperfusion (I/R) in rats. Methods Forty-five rats were randomly divided into sham group, whole cerebral I/R group and I/R plus CGRP injected into carotid group. The acute global cerebral ischemia model was prepared according to Pulsinelli. Spectrophotometry was applied to measure the activities of SOD and NOS, and the content of MDA in brain tissue. Results Compared with those in the sham group, the activity of NOS increased, and the activity of SOD and the content of MDA decreased in I/R group (P<0.05 or 0.01). Compared with the I/R controls, CGRP significantly reduced the content of MDA in the rat brain tissue (P<0.05), while the activities of SOD and NOS were not significantly altered (P>0.05). Conclusions These results suggest that CGRP might provide significant protection against cerebral I/R injury, the mechanisms of which may be related to its inhibiting action on the lipid peroxidation during the process of cerebral I/R.