Effect Of Caffeine On Acupuncture Analgesia And Pain-Related Molecules In Hypothalamus

Objective:To study the influence of caffeine on the acupuncture analgesia and pain-related molecules in the hypothalamus.Methods:The male C57BL/6J mice were taken as animal model of inflammatory pain. Then use Dynamic Plantar Aesthesiometer to evaluate the paw latency of them, And they showing a decline on paw withdrawal latency were randomly divided into control group, model group, model+EA group (model-EA group), model+EA+caffeine group (model-caffeine-EA group). The mice of inflammatory pain were treated with electroacupuncture after oral administration of caffeine (70 mg/Kg/day). Using electroacupuncture in the acupoint ST36 (Zusanli). Then the model-EA group and the model-caffeine-EA group were given the electroacupuncture treatment on ST36 (Zusanli) with HANS Acupont and Nerves Stimulator (HANS-200) using 2/100Hz and 0.2mA for 15 min each tine and one time a day,which lasted for 11 days. After the 11 days electroacupuncture,put to death animals materials under test. Use the real-time fluorescence quatititive PCR-Array to test the change of the hypotalamus pain-related molecules.Result:(1)The results of effect of caffeine on the analgesic effect of electroacupunctureComparison between groups:After the model establishment third,compared with the control group,the paw withdrawa latency of the model group,the model-EA group and the model-caffeine-EA group were siginficantly reduced (P<0.000),but the paw withdrawa latency of the model group,the model-EA group and the model-caffeine-EA group were not statistically significant(P>0.05).After the model establishment seven,Compared with the model group,there was statistical significance in the paw withdrawa latency of the model-EA group (P<0.000);Compared with the model group,there was not statistical significance in the paw withdrawa latency of the model-caffeine-EA group(P>0.05).Compared with the model-EA group, there was statistical significance in the paw withdrawa latency of the model-caffeine-EA group (P<0.000).After the model establishment the thirteenth and fourteenth day,Compared with the model group,there was statistical significance in the paw withdrawa latency of the model-EA group (P<0.000);Compared with the model group,there was not statistical significance in the paw withdrawa latency of the model-caffeine-EA group(P>0.05).Compared with the model-EA group, there was statistical significance in the paw withdrawa latency of the model-caffeine-EA group (P<0.001).Comparing in the group:In the model group,compared with the pain threshold of the third day of pain threshold,there was improved in the model group in seven day (P<0.001);Compared with the pain threshold of the seven day after establishment of model,there was statistically significant (P< 0.000) in the pain threshold of the hirteenth and fourteenth day,but there was not statistically significant between the thirteenth and fourteenth day (P>0.05).In the model-EA group,compared with the pain threshold of the third day of pain threshold,there was statistical significance in the model-EA group in seven day (P<0.000);Compared with the pain threshold of the seven day after establishment of model,there was statistically significant (P< 0.000) in the pain threshold of the thirteenth and fourteenth day,but there was not statistically significant between the hirteenth and fourteenth day (P>0.05).In the model-caffeine-EA group,compared with the pain threshold of the third day of pain threshold,there was improved in the model-caffeine-EA group in seven day (P<0.05);Compared with the pain threshold of the seven day after establishment of model,there was statistically significant (P< 0.001) in the pain threshold of the thirteenth and fourteenth day,but there was not statistically significant between the thirteenth and fourteenth day (P>0.05).(2)The results of changes in pain-related molecules in the hypothalamusCompared with the control group, there were up-regulated 13 genes and 5 genes were down-regulated in model group;Compared with the model group, there were up-regulated 6 genes and 1 genes was down-regulated in EA group;Compared with the model group,there were up-regulated 24 genes and 1 gene were down-regulated in the model-coffeine-EA group; All of the above changes genes related to the caffeine effect on electroacupuncture analgesia was Ngf.Compared with the control group,the pain-molecular Ngf was up-regulation in the the model group.while compared with the model group,the pain-molecular gense Ngf was declined.Compared with the control group,the expression of pain-molecular genes Ngf unchanged in the model-coffeine-EA group.Conclusion:(1) The electroacupuncture has definite analgesic effect on pain-inflammatory;(2)Intake caffeine (70 mg/Kg/day) can inhibit the analgesic effect of electroacupuncture;(3)The effect of caffeine on the analgesic effect of electroacupuncture may be related to the expression of Ngf gene in hypothalamus.