Lammers W J, Ahmad H R, Arafat K
Department of Physiology, Faculty of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.
Am J Physiol. 1996 Apr;270(4 Pt 2):F567-74. doi: 10.1152/ajprenal.1996.270.4.F567.
In renal pelvis preparations isolated from the sheep, the location of the pacemaker and the pathway of conduction of the electrical impulse in the pelvis were analyzed in detail. An electrophysiological acquisition system was used allowing simultaneous recordings from 240 extracellular electrodes. Reconstruction of the spread of activity showed that the site of the pelvis pacemaker was, in virtually all cases, located at the pelvicalyceal border and never in the body of the pelvis or in the area of the pelviureteric junction. One single pacemaker was responsible for a particular spread of activation, and fusion of activity originating from two or more pacemakers did not place. Furthermore, spontaneous shifts of the pacemaker could occur from one site to another along the pelvicalyceal border. Conduction from the site of the current pacemaker to the pelviureteric junction and the ureter was slow, inhomogeneous, and contorted. Multiple instances of partial or total conduction block were seen at all levels in the pelvis and were not restricted to the pelviureteric junction. The occurrence of the conduction block did not seem to be related to the length of the preceding interval, implying that the refractory period did not play a major role in the genesis of intrapelvic conduction block. In conclusion, high-resolution mapping of the renal pelvis is possible and reveals location and behavior of the pacemaker and documents inhomogeneities in conduction and conduction block.
在从绵羊分离出的肾盂标本中，详细分析了肾盂中起搏器的位置以及电冲动的传导途径。使用了一种电生理采集系统，可同时从240个细胞外电极进行记录。活动传播的重建显示，几乎在所有情况下，肾盂起搏器的位置都位于肾盂输尿管边界，而从未在肾盂主体或肾盂输尿管连接处区域。单个起搏器负责特定的激活传播，并且未发生源自两个或更多起搏器的活动融合。此外，起搏器可能会沿着肾盂输尿管边界从一个部位自发转移到另一个部位。从当前起搏器部位到肾盂输尿管连接处和输尿管的传导缓慢、不均匀且扭曲。在肾盂的各个层面都观察到多次部分或完全传导阻滞的情况，并且不仅限于肾盂输尿管连接处。传导阻滞的发生似乎与前一个间期的长度无关，这意味着不应期在肾盂内传导阻滞的发生中不起主要作用。总之，肾盂的高分辨率标测是可行的，它揭示了起搏器的位置和行为，并记录了传导和传导阻滞的不均匀性。
