OBJECTIVETo observe the effects and duration of electroacupuncture on the mechanical pain threshold induced by paclitaxel and explore its analgesic mechanism.

METHODSSixty-four C57BL/6J male mice were randomly divided into 4 groups, a normal+sham EA group, a normal+EA group, a medicine+sham EA(Med+ sham EA) group, a medicine + EA (Med + EA) group, 16 cases in each group. The model of chemotherapy-induced peripheral neuropathy was established with paclitaxel intraperitoneal injection on the 1st, 3rd, 5th, 7th day in the Med + sham EA group and the Med + EA group. EA of 30 min was used on bilateral "Zusanli (ST 36)" on the 9th, 11th, 13th, 16th, 18th, 20th, 23rd, 25th, 27th, 30th day in the EA groups, 2 Hz/100 Hz and 1~ 1.5 mA. Acupuncture was applied on the same acupoint at the same times in the sham EA groups. Mechanical pain thresholds were tested by VonFrey before and after model establishment, namely on the 8th, 14th; 21st and, 28th day. The heart blood of 8 mice was drawn quickly to collect serum in every group on the 31st day, and the contents of tumor necrosis factor α (TNF-α), interleukin-1α (IL-1α), interleukin-1β (IL-1β) in proinflammatory cytokine were examined by ELISA. Mechanical pain thresholds were tested by VonFrey for the rest 8 mice of each group until there was no apparent difference in the two paclitaxel groups once a week,namely on the 35th, 42nd, 49th day.

RESULTSThe pain thresholds of each group were not statistically different before model establishment (P > 0.05). After model establishment (on the 8th day), thresholds of the paclitaxel groups were lower than those of the normal groups (all P < 0.05). After EA, the mechanical pain thresholds of the Med + EA group were higher than those of the Med + sham EA group at all the time points, and there was statistical difference on the 14th, 21st and 28th day (all P < 0.05). The analgesic effect was lasting to the 49th day. The contents of TNF-α, IL-1α, IL-1β of the Med + EA group were decreased than those of the Med+sham EA group in different degree, with statistical significance of IL-1α (P < 0.05).

CONCLUSIONEA can effectively treat paclitaxel-induced peripheral neuropathy,and the analgesic mechanism is probably related to decreasing the proinflammatory cytokine.

Acupuncture Points ; Animals ; Antineoplastic Agents ; administration & dosage ; adverse effects ; Electroacupuncture ; Humans ; Interleukin-1beta ; genetics ; metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Neoplasms ; drug therapy ; Peripheral Nervous System Diseases ; etiology ; genetics ; metabolism ; therapy ; Tumor Necrosis Factor-alpha ; genetics ; metabolism

Objective To compare the analgesic effects of fire needling, conventional acupuncture and acupoint catgut embedding in rats with rheumatoid arthritis.Methods Fifty healthy male SD rats were randomized into control, model, acupuncture, fire needling and catgut embedding groups, 10 rats each. A SD rat model of rheumatoid arthritis was made by intracutaneous injection of complete Freund’s adjuvant into the right hind foot pad. Right Kunlun and Zusanli were selected as therapeutic points in the three groups and given fire needling, acupuncture or catgut embedding. The right paw mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) were used as observation indices and measured in every group of rats at one day before and four days after model making and at one, seven and fourteen days after the beginning of treatment. Rat paw inflammatory tissues were separated after the completion of treatment. The IL-1 and TNF-α contents of them were measured. Results There were statistically significant differences in MWT and TWL between the model, acupuncture, fire needling or catgut embedding group and the control group after model making, and one, seven and fourteen days of treatment (P<0.01). There were statistically significant differences in MWT and TWL between the fire needling group and the model, acupuncture or catgut embedding group after one, seven and fourteen days of treatment (P<0.01,P<0.05). There was a statistically significant difference in MWT between the acupuncture or catgut embedding group and the model group after one, seven and fourteen days of treatment (P<0.01). There was a statistically significant difference in TWL between the acupuncture or catgut embedding group and the model group after seven and fourteen days of treatment (P<0.01,P<0.05). There were statistically significant differences in IL-1 and TNF-α contents between the model, acupuncture, catgut embedding or fire needling group and the control group after model making (P<0.01). after treatment, there were statistically significant differences in IL-1 and TNF-α contents between the acupuncture, catgut embedding or fire needling group and the model group and between the acupuncture or catgut embedding group and the fire needling group (P<0.05).Conclusions Fire needling can raise pain threshold in rats with rheumatoid arthritis. It alleviates rheumatoid arthritis-induced chronic pain by reducing the inflammatory factor content of affected muscular tissues.