Grill W M, Bhadra N, Wang B
Department of Biomedical Engineering, Applied Neural Control Laboratory, C.B. Bolton Building, Room 3480, Case Western Reserve University, Cleveland, OH 44106-4912, USA.
Brain Res. 1999 Jul 31;836(1-2):19-30. doi: 10.1016/s0006-8993(99)01581-4.
Experiments were conducted to measure the bladder and urethral pressures evoked by intraspinal microstimulation of the sacral segments (S1-S2) in neurologically intact, chloralose anesthetized adult male cats. The bladder pressure was measured with a superpubic catheter and the urethral pressure was measured simultaneously at the level of the urethral sphincter and at the level of the penis using a two-element micromanometer. Intraspinal stimuli (typically 1 s, 20 Hz, 100 microA, 100 microseconds) were applied with activated iridium microwire electrodes in ipsilateral segments and intersegmental boundaries with a 250 micrometer mediolateral resolution and a 200 micrometer dorsoventral resolution. Increases in bladder pressures were generated by microstimulation in the intermediolateral region, in the lateral and ventrolateral ventral horn, and around the central canal. Simultaneous increases in urethral pressure were evoked by microstimulation in the ventrolateral ventral horn, but not at the other locations. Small reductions in urethral pressure (<10 cm H(2)O) were evoked at locations in the intermediate laminae and around the central canal. The magnitude of these pressure reductions was weakly dependent on the stimulus parameters. Stimulation around the central canal produced bladder contractions with either no change or a reduction in urethral pressure and voiding of small amounts of fluid. These results demonstrate that regions are present in the spinal intact anesthetized cat where microstimulation generates selective contraction of the bladder without increases in urethral pressure and that regions are present where microstimulation generates small reductions in urethral pressure.
在神经功能完整、水合氯醛麻醉的成年雄性猫身上进行了实验，以测量经脊髓微刺激骶段（S1 - S2）诱发的膀胱和尿道压力。膀胱压力通过耻骨上导管测量，尿道压力使用双元件微压力计在尿道括约肌水平和阴茎水平同时测量。经脊髓刺激（通常为1秒，20赫兹，100微安，100微秒）通过激活的铱微丝电极施加于同侧节段和节段间边界，在内外侧方向上的分辨率为250微米，在背腹方向上的分辨率为200微米。在中间外侧区域、外侧和腹外侧腹角以及中央管周围进行微刺激可引起膀胱压力升高。在腹外侧腹角进行微刺激可同时引起尿道压力升高，但在其他位置则不会。在中间层和中央管周围的位置可诱发尿道压力小幅降低（<10厘米水柱）。这些压力降低的幅度在一定程度上依赖于刺激参数。在中央管周围进行刺激会产生膀胱收缩，尿道压力要么没有变化，要么降低，同时会排出少量液体。这些结果表明，在脊髓完整的麻醉猫中，存在一些区域，微刺激可在不增加尿道压力的情况下选择性地引起膀胱收缩，也存在一些区域，微刺激可使尿道压力小幅降低。
