Blok B F, van Maarseveen J T, Holstege G
Department of Anatomy and Embryology, Faculty of Medical Sciences, University of Groningen, The Netherlands.
Neurosci Lett. 1998 Jun 12;249(1):68-70. doi: 10.1016/s0304-3940(98)00382-6.
Stimulation of the pontine micturition center (PMC) results in micturition, i.e. an immediate relaxation of the urethral sphincter and a contraction of the detrusor muscle of the bladder. The PMC generates the bladder contraction by way of a direct excitatory pathway to the parasympathetic bladder motoneurons in the sacral cord. The idea is that the PMC produces the relaxation of the urethral sphincter via direct projections to GABAergic neurons in the dorsal gray commissure (DGC), which, in turn, inhibit the urethral sphincter motoneurons. According to this hypothesis, electrical stimulation in the DGC in three cats should result in relaxation of the urethral sphincter. The results were in total agreement with this concept. During DGC stimulation a sharp decrease of the urethral pressure was found, the strength of which depended completely on the amplitude of the electrical stimulation.
刺激脑桥排尿中枢（PMC）会导致排尿，即尿道括约肌立即松弛，膀胱逼尿肌收缩。PMC通过一条直接的兴奋性通路作用于骶髓中的副交感神经膀胱运动神经元，从而引发膀胱收缩。有一种观点认为，PMC通过直接投射到背侧灰质连合（DGC）中的GABA能神经元，使尿道括约肌松弛，而这些GABA能神经元反过来又会抑制尿道括约肌运动神经元。根据这一假说，对三只猫的DGC进行电刺激应会导致尿道括约肌松弛。结果与这一概念完全相符。在刺激DGC期间，发现尿道压力急剧下降，其强度完全取决于电刺激的幅度。
