Hosokawa H, Kaseda M
Department of Urology, Nihon University School of Medicine.
Nihon Hinyokika Gakkai Zasshi. 1993 Mar;84(3):440-9. doi: 10.5980/jpnjurol1989.84.440.
The cholinergic and adrenergic neurotransmitters have been shown to play an important role for the contraction as well as the relaxation of the bladder neck and posterior urethra. However, other neurotransmitters were suggested to participate in the action of the lower urinary tract. Therefore, animal experiments were carried out to clarify the physiological function of vasoactive intestinal polypeptide (VIP). In vitro experiments, the smooth muscle obtained from the bladder neck and the urethra of female porcine were exposed to the transmural electric field stimulation with or without anti-cholinergic, anti-adrenergic drugs, VIP or anti-VIP. In vitro experiments, electric stimulation showed the temporary relaxation of the smooth muscle due to the discharge of several kinds of neurotransmitters. Moreover, the muscle relaxation continued with the addition of VIP after the administration of the anticholinergic and the antiadrenergic agents. The urethral pressure was observed using male cat in order to demonstrate the action of VIP in vivo. The intraarterial infusion of VIP showed mainly the reduction in the posterior urethral pressure. Furthermore, the administration of anti-VIP was attempted to counteract the VIP action induced by the electrostimulation. As the result, the intra-urethral pressure tended to decrease after administration of the anti-VIP infusion. From the present investigation, VIP proved to be one of the non-cholinergic and non-adrenergic neurotransmitter through pelvic nerve system, and was thought to play an important part in the muscle relaxation of the bladder neck and the posterior urethra.
胆碱能和肾上腺素能神经递质已被证明在膀胱颈和后尿道的收缩及舒张过程中发挥重要作用。然而，有研究表明其他神经递质也参与下尿路的活动。因此，开展了动物实验以阐明血管活性肠肽（VIP）的生理功能。在体外实验中，将取自雌性猪膀胱颈和尿道的平滑肌暴露于有或无抗胆碱能、抗肾上腺素能药物、VIP或抗VIP的跨壁电场刺激下。在体外实验中，电刺激显示由于多种神经递质的释放，平滑肌出现暂时舒张。此外，在给予抗胆碱能和抗肾上腺素能药物后，添加VIP可使肌肉舒张持续。为了证明VIP在体内的作用，使用雄性猫观察尿道压力。动脉内注入VIP主要显示后尿道压力降低。此外，尝试给予抗VIP以抵消电刺激诱导的VIP作用。结果，注入抗VIP后尿道内压力有降低趋势。从目前的研究来看，VIP被证明是通过盆神经系统起作用的非胆碱能和非肾上腺素能神经递质之一，并且被认为在膀胱颈和后尿道的肌肉舒张中起重要作用。
