Objective： Needling lumbosacral acupoints could regulate unstable bladder （USB）. The present study is to observe the ambulatory urodynamics changing of needling Huiyang （BL 35） on USB to provide scientific basis for the relative theory of acupoint and Zang-fu organs, and the rule of acupuncture treatment. Methods： Unstable bladder model were prepared in 80 Wistar rats, and then they were randomly divided into treatment group （n=40） and model group （n=40）. The urodynamics were monitored respectively at 2 h, 6 h, 12 h and 24 h after acupuncture and the results were analyzed. Results： After acupuncture Huiyang （BL 35）, the compliance of bladder were superior to that of model group at 2 h, 6 h and 12 h, respectively （P〈0.05）, and the bladder volume were superior to that of model group at 2 h and 12 h, respectively （P〈0.05）. After acupuncture Huiyang （BL 35）, the compliance and volumn of bladder at 12 h were superior to those at other time （P〈0.05）. Twenty-four hours later, the effect of acupuncture on urodynamics decreased. Conclusion： Needling Huiyang （BL 35） could improve the urodynamics of USB, including improving the compliance of bladder and increasing the volume of bladder. Acupuncture Huiyang （BL 35） had the most effect at 12 h.
