Dubuc R, Rossignol S
Département de Physiologie, Faculté de Médecine, Université de Montréal, Que, Canada.
Brain Res. 1989 Jul 10;491(2):335-48. doi: 10.1016/0006-8993(89)90068-1.
In a previous paper, we have reported that 4-aminopyridine (4-AP, i.v., 10 mg/kg) induces in decerebrate spinal and paralyzed cats, a sustained rhythmic activity (2.5-8.5 Hz) in various muscle nerves. We describe here that similar discharges are recorded from the proximal stump of cut cutaneous nerves. The latter rhythmic activity arises from intense antidromic discharges in the dorsal roots. The rhythmic discharges are recorded from dorsal roots of both spinal cord enlargements as well as from thoracic roots. The rhythmic activity is highly synchronous among adjacent dorsal roots. Bilateral activity is also highly cross-correlated, but may be dissociated by unilateral stimulation of one dorsal root. It is not yet possible to determine the precise site where the antidromic discharges recorded from the dorsal roots are generated. 4-AP could act directly at the terminal level of the primary afferents or could activate interneurons impinging upon the terminals.
在之前的一篇论文中，我们报道了4-氨基吡啶（4-AP，静脉注射，10毫克/千克）在去脑脊髓和瘫痪的猫身上，能在各种肌肉神经中诱导出持续的节律性活动（2.5-8.5赫兹）。我们在此描述，从切断的皮神经近端残端也记录到了类似的放电。后者的节律性活动源于背根中的强烈逆向放电。节律性放电记录于脊髓两个膨大的背根以及胸段背根。相邻背根之间的节律性活动高度同步。双侧活动也高度相互关联，但可通过单侧刺激一根背根而分离。目前尚无法确定从背根记录到的逆向放电产生的确切部位。4-AP可能直接作用于初级传入纤维的终末水平，或者激活作用于终末的中间神经元。
