Abstract:

Objective   To investigate the influences of lymphostatic encephalopathy(LE) on the  autonomic nervous system. Methods   The model of LE was established by occluding lymphatic vessels and removing both shallow and deep cervical lymph nodes in Wistar rats. The rats were randomly divided into the shamoperation(SHAM) group and the LE group, 40 rats in each group. The electrocardiogram (ECG) (lead II) of rats was synchronously recorded by the PowerLab system on postoperative days 1, 7, 14 and 21. Heart rate variability (HRV) was analyzed with ECG signals. Brain morphology of the rostral ventrolateral medullas (RVLM) was observed by a light microscope and an electron microscope. eNOS protein expression in RVLM was determined by Western blot. Results   Compared with the SHAM group, HRV was significantly increased, while HR was reduced（P<0.05）. The vagus nerve modulation was enhanced, necrosis of neurons appeared in RVLM, permeability of capillaries was increased, and brain tissue edema occurred.  Ultrastructural observation showed neuronal apoptosis and myelin sheath disintegration. Protein expression of eNOS was significantly decreased. Conclusion   LE induces injury to the cerebral tissue and autonomic nervous regulation, and the mechanism may be related to down-regulation of eNOS expression.

Key words:  Lymphostatic encephalopathy; Heart rate; Nitric-oxide synthase; Rostral ventrolateral medulls