OBJECTIVETo observe the intestinal movement of transient receptor potential vanilloid 1 or vanilloid receptor 1 (TRPV1) knockout mice after stimulated by electroacupuncture (EA), and to primarily explore the roles of TRPV1 receptor in the jejunal motility regulated by acupuncture.

METHODSNormal wild-type CL57BL/6 and TRPV1 gene knockout mice were recruited in two groups, the B6 group and the TRPV1 group, 15 in each group. The thermal threshold and the mechanical pain threshold were respectively detected using JL-F digital photo thermal analyzer instrument and ALMEMO2450 machine. The difference between the two thresholds were compared. Meanwhile, a self-made pressure head was placed in the jejunum. The internal pressure was monitored. When the pressure was stable, 2 mA 2/15 Hz EA at Quchi (LI11), Tianshu (ST25), Shangjuxu (ST37), and Dachangshu (BL25) to observe the changes of intestinal pressure value between before and after EA. The curve of internal pressures was recorded.

RESULTS(1) The stimulation of light/heat and mechanical stimulation were obviously slowed in the TRPV1 group than in the B6 group (P < 0.01). (2) In the intestinal pressure observation experiment, the bowel movement was not obviously seen in the two groups when acupunctured at Quchi (LI11) and Shangjuxu (ST37) (P > 0.05). (3) Acupuncture at Tianshu (ST25) and Dachangshu (BL25) of TRPV1 knockout mice could lead to intestinal movement (P < 0.05), mainly inhibited bowel movement. The changing degree was equivalent to that of B6 mice.

CONCLUSIONSUnder the physiological condition, TRPV1 might be mediated by thermal and mechanical stimulation. But TRPV1 mediated acupuncture effect was quite complex, indicating TRPV1 mice might be one of intestinal movement mediating factors.