RESUMO
Objective To study the effects of electrical stimulation of efferent vagus nerve on the endotoxic shock in rabbits. Method Sixteen Newzealand rabbits were randomly divided into 2 groups, namely group S as the stimulation group and group C as the control group). Rabbits were subjected to bilateral cervical vagotomy and had challenge with intravenous injection of lipopolysaccharide (LPS) (E. COLI O111: B4 , DIFCO, USA) in a dose of 600 μg/kg. The distal end of the left vagus nerve trunk was connected to an electric stimulator with bipolar electrode and controlled by an acquisition system. Stimuli with stable voltage (10 V,5 Hz,5 ms) were applied twice to the nerve for 10 minutes just before and after the administration of LPS in group S. At the time before and after the infusion of LPS 30 min,60 min, 120 min, 180 min,240 min and 300 min respectively, the heart rate(HR)and the mean arterial blood pressure (MABP) in each animal were recorded, and blood samples were taken for measuring serum tumor necrosis factor-αa(TNF-α) and interleukin-10 (IL-10). Results Compared with group C,the electrical stimulation of efferent vagus nerve could significantly attenuated the LPS-induced hypotension and de-creased the contents of TNF-α[(38.12±7.85) pg/mL vs. (55.12±7.89) pg/mL, P <0.01], but increased the contents of IL-10[(55.12±9.37)pg/mL vs. (40.15±5.44) pg/mL, P <0.01]afar LPS challenge. Conclusions The stimulation of the efferent vagus nerve can down-regulate systemic TNF-α, production and attenu-ate the development of shock after LPS challenge.