Yunpi prescription reduces excitability of VMN neurons in anorexic rats

    DU Yongª²Ping, WANG Xia, ZHANG Yueª²Ping, NIU Yu

    1Department of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China, 2Department of Health Statistics, School of Preventive Medicine, 3Department of Child Diseases, 4Department of Traditional Chinese Medicine, Xijing Hospital, Fourth Military Medical University, Xi¬ðan 710033, China

    ¡¾Abstract¡¿ AIM: To explore the role of Yunpi, a traditional Chinese prescription, in reducing the sensitivity of the VMN neurons to the peripheral afferent signal in anorexia rats.METHODS: The anorexic rat model was established by feeding rats with specially prepared forage for 1 week followed by daily intragastric administration of liquid extract of Yunpi prescription for 3 weeks. The extracellular recording from rat VMN was then conducted to characterize the responses of stimulating gastric vagal nerve and intravenous injection of sulfated cholocystokinin octapeptide (CCKª²8) in the control, model and Yunpi treated groups. RESULTS: The duration of the VMN neuronal excitation to the gastric vagal nerve stimulation in model group was significantly longer than that in control group (P<0.05) and the number of CCKª²sensitive neurons significantly increased with the decrease of stimulation intensity in model group compared with that in control group (P<0.05). However, there was no significant difference in the responses of VMN neurons to the stimulation of gastric vagal nerve and the CCK administration between the Yunpi treated group and the control group. CONCLUSION: Yunpi prescription can reduce the sensitivity of VMN neurons to the negative feedback signal from the periphery and improve the appetite of the anorexia rats. ......