Ultrastructural Diagnosis of Neuropathic Detrusor Overactivity: Validation of a Common Myogenic Mechanism

Different types of cell junctions have been described in lower urinary tract musculature. Intermediate cell junctions (ICJ) predominate the normal mammalian detrusor(including that of the human), mediating coupling of smooth muscle cells (cell-to-cell transmittal of contraction) mechanically.7,8,14,15 ICJ consist of strictly parallel sarcolemmae of adjacent cells, with 25 to 60 nm separation gaps that contain central linear densities. They are bordered by paired symmetrical dense plaques in the subsarcolemmal sarcoplasm, and anchor obliquely slanted myofilaments to the cell membranes (Fig. 1).