【摘要】 目的　研究猫在低速弹所致的颅脑枪弹损伤 (CMW)后 ,L-精氨酸 (L- Arg)对早期脑微循环的影响。方法　用改良 Carey法制作猫 CMW模型 ,将 12只动物分为单纯损伤组和 L- Arg治疗组 ,观察两组损伤前后软脑膜微血管的管径 (D)、血流速度 (V)、血流量 (Q)及脑组织病理学的变化。结果　 1单纯损伤组 ,微动脉 Da、Va和Qa在伤后 5～ 2 0 min期间明显降低 ,4 5 m in后逐渐恢复 ,并且 Qa和 Da超过伤前水平 ;微静脉 Dv超过伤前水平但是无明显差异 ,而 Vv伤后一直偏低 ,Qv在伤后 2 0 min内降低 ,4 5 m in后超过伤前呈淤血状态。 2 CMW后 ,L-Arg治疗组 Da在 5 m in时即出现扩张 ,Qa在 2 0 min后开始增加 ,一直持续到 5 h;Dv和 Qv在 2 0 m in后一致显著增加。 3伤道对侧皮层可见点状出血、微血栓形成、神经细胞肿胀 ,L- Arg治疗组变化较单纯损伤组轻。结论　CMW后早期出现微循环障碍 ,导致脑缺血缺氧 ,引起神经功能障碍 ;注射 L- Arg后 ,可以使微血管的管径和血流量增加 ,减轻颅脑损伤引起的脑微循环障碍和病理损害。更多还原

【Abstract】 Objective To study the alterations of cerebral microcirculation and the effect of L-Arginine after craniocerebral missile wound(CMW) at early stage in cats. Methods The CMW animal model in cat was constructed by Carey method. Altogether 12 mongrel cats with either sex were divided into the CMW group and the L-Arginine treatment group. The caliber(D), velocity (V) and blood flow (Q) of pial microvessels and pathological examination of brain tissue at 10 min before CMW and from 5 min to 5 h after CMW were evaluated in each group. Results ①In CMW group, although the Da,Va and Qa of pial arteriole decreased from 5 to 20 minutes, Da and Qa elevated at 90 minutes after CMW. There were no significant changes in the Dv of pial venule, but the levels of Vv and Qv were lower at 5 min and 20 min after CMW. Qv increased from 45 min to 3 h after CMW. The pial venules were in congestion situation. ②In the L-Arginine treatment group, the pial aterioles persistently dilated after CMW. The blood flow of pial aterioles increased at 20 min after CMW and the higher level lasted 5 h. Similarly, the dilation of pial venules was observed, and the blood flow increased at 20 min after the injury, followed by venules constriction temporarily. ③Petechial hemorrhage, microthrombosis and nerve cell swelling were found in the cortex on the opposite side of the trauma area. The pathological changes were less severe in the L-Arginine treatment group than those in the CMW group.Conclusion At the early stage after CMW, there are obstructions to cerebral microcirculation, which induce brain ischemia, hypoxia and secondary failure of cerebral function. The mechanism by which L-Arginine alleviates the impaired cerebral microcirculation may lie in the vascular activation of L-Arginine-NO system.更多还原