Acupuncture induces biochemical releases that alleviate urinary retention disorders. A recent laboratory study measured the effects of needling acupuncture points UB40 (Weizhong), SP9 (Yinlingquan) and SP6 (Sanyinjiao) on rabbits with urine retention. Electroacupuncture was applied between 2 Hz to 15 Hz bilaterally to the acupuncture points for 20 minutes, respectively. The findings measured increases in bladder ATP and intravesical pressure, the pressure exerted on the contents of the urinary bladder. Bladder ATP is involved in urinary bladder volume reflexes along with intravesical pressure. The researchers conclude, "EA (electroacupuncture) of UB40, SP6 and SP9 can significantly raise intravesical pressure and bladder ATP content in urine retention rabbits, which may contribute to its effect in improving urinary retention."

Reference:
Zhen Ci Yan Jiu. 2012 Aug;37(4):291-5. [Effects of electroacupuncture of "Weizhong" (BL 40), "Sanyinjiao" (SP 6) and "Yinlingquan" (SP 9) on intravesical pressure and bladder adenosine triphosphate content in rabbits with acute urinary retention]. Cheng LL, Wu CY, Sui MH. School of Acu-moxibustion and Massage, Beijing University of Chinese Medicine, Beijing, China.