家兔急性脑干出血与急性高颅压所致应激性溃疡的比较研究

Comparison of acute brain stem hemorrhage and stress ulcer induced by acute intracranial hypertension in rabbits

目的:探讨家兔脑干出血合并应激性十二指肠溃疡出血的发生机制,及高颅压对十二指肠黏膜血流改变的影响。方法:雄性日本大耳白家兔(1.5～1.8kg)80只进行活体实验,使用250g/L乌拉坦静脉麻醉,施行颅骨打孔手术复制急性脑干出血动物模型。施行脑室插管手术,做成急性持续性颅压高动物模型。手术显露颈部交感神经干及迷走神经干,计测在一定的侧脑室压力负荷条件下(脑脊液压4.788kPa,持续1min)的颈部交感神经及颈部迷走神经放电变化,解析电活动强度的变化。使用微循环显微镜血管摄像装置及微循环电视录像系统连续测定脑干出血条件下的十二指肠黏膜绒毛的充血程度,使用计算机Photoshop软件连续解析同一绒毛同一坐标点上的红色色度坐标值的经时变化,做成十二指肠绒毛同一位点上的红色色度坐标值的经时移行曲线。使用同一系统连续观测颅压高条件下的十二指肠黏膜充血程度的变化。结果:①此实验条件下,显示脑干出血负荷后的十二指肠黏膜的红色色度减低(苍白)及与之同步的微小形态改变。②急性颅压高(4.788kPa)导致迷走神经放电活动增强,交感神经放电频率减低。十二指肠黏膜绒毛瘀血及点状出血。十二指肠黏膜绒毛的显著扭曲、移位。结论:本实验条件下,家兔脑干出血负荷后侧脑室压增高。

AIM:To explore the occurring mechanism of brainstem hemorrhage complicated with stress ulcer and hemorrhage in duodenal mucosa in rabbits, and the effects on blood stream in duodenal mucosal villi under intracranial hypertension conditions. METHODS:A total of 80 Japanese white rabbits with long ears(male,1.5 to 1.8 kg) were used for vivi perception,and 250 g/L Urethane was used for intravenous anesthesia.Rabbits were given a cranial fenestration for a acute brain stem hemorrhage to copy animal model, and were given an operation of intubation into cerebral ventricle for an animal model of acute continuous intracranial hypertension.The operation showed jugular sympathetic trunk and vagus trunk, whose changes of neural discharge were measured under the load of lateral ventricle with cerebrospinal fluid pressure 4.788 kPa) for one minute,and the intensity of electrical activities were analysed. Microcirculation microscopic blood vessel telecamera and microcirculation TV video system were used to determine the congestive degree of duodenal mucosa under the brain stem hemorrhage conditions.Computer and Photoshop software were used to analyze the continuous changes of the red color coordinate of the same villus on the same coordinate point to make a duodenal villi's movement curve of the red color coordinate on the same point with time.The changes of congestive degree in duodenal mucosa were recorded continuously with the same methods under intracranial hypertension conditions. RESULTS:①Reduction(pallor) in the red color of duodenal mucosa and synchronous slight changes in shape after brain stem hemorrhage.②Acute intracranial hypertension(4.788 kPa) caused neural discharge of vagus nerve increased and the frequency of neural discharge in sympathetic nerve decreased.Meanwhile, changes of congestive degree and dotted hemorrhage twisted and transposed of duodenal mucosal villi were also found. CONCLUSION:In this experiment, intracranial pressure of lateral ventricle is increased under the brainstem hemorrhage conditions.The occurring mechanism of duodenal mucosal ulcer is probably related to intracranial hypertension or local intracranial hypertension.Acute intracranial hypertension can cause changes of neural discharge of sympathetic and parasympathetic nerve,which induce spasmodic contraction of gastrointestinal smooth muscle, congestion and dotted hemorrhage in duodenal mucosa, and stress ulcer and hemorrhage of digestive tract finally.