实验性脑淋巴引流障碍对大鼠血压、心率调节功能的影响

The affuence on BP and the HR regulation after experimental cervical Lymphatic Blockase in Rat

目的：探讨阻断颈部淋巴引流大鼠血压、心率、整体调节功能的变化。方法：将Ｗｉｓｔａｒ大鼠分成两组：对照组（ｎ＝１０）接受假手术；淋巴引流阻断组（ｎ＝１０）结扎颈浅及颈深淋巴管并摘除淋巴结以造成淋巴性脑水肿。两组均在术后第７天进行正立位倾斜应激试验及倒立位倾斜应激试验，其间连续测定动脉血压、心率、Ⅱ导ＥＣＧ、顶部ＥＥＧ及其能量曲线等，并观察整体压力感受器反射灵敏度（ＢＳ）。结果：对照组大鼠正立位初动脉血压降低，尔后迅速恢复正常；倒立位初动脉血压升高，但随后迅速回降。当阻断两侧颈总动脉血流时，动脉血压升高，ＥＥＧ不变。淋巴引流阻断组大鼠正立位及倒立位时动脉血压均持续显著低于正常水平，出现心律紊乱，ＢＳ降低。阻断两侧颈总动脉后动脉血压反而降低，脑电图变平坦，脑电能量曲线几乎减小至零。结论：大鼠颈淋巴引流障碍，可导致血压、心率、ＥＥＧ调节功能减弱，压力感受器灵敏度降低，易产生体位性低血压。

Objective: To investigate the alternations of regulatory function of the cardiovascular system after experimental cervical lymphatic blockage in rats with passive posture tilting stress test (PPTST). Methods: Wistar rats were divided into control group (n=10) which accepted sham-operation and cervical lymphatic blockage group (CLB group,n=10), in which the cervical lymphatic vessels were blockaged and lymphatic nodes were removed. In both groups 7 days after operation the regulatory fuction of cardiovascular system was determined with PPTST. PPTST included head-up stress test (HUST) and head-down stress test (HDST). During both tests the arterial blood pressure (BP) and heart rate (HR) were continously recorded. The total baroreceptor reflex sensitivity (BS) was calculated. In 7 animals the response of EEG and BP to an incomplete cerebral isehemia were observed. Results: In control group at the beginning of HUST BP decreased, and then rapidly restored to normal level. At the beginning of HDST, BP increased, and then decreased rapidly, after incomplete cerebral ischemia EEG was unchanged and the BP was increased by a baroreceptor reflex. In CLB group both during HUST and HUDT the BP falled markedly. In some animals arrhythmia occured. BS greatly decreased. After blocking the blood flow in the carotid arteries the BP decreased the EEG became isoelectric. Conclusion: Experimental cervical lymphatic blockage may lead to disturbance of homeostasis of the cardiovascular regulation, the BP,HR and BS decreased and may lead to posture hypotension.