Expression of Occludin in Porcine Renal Epithelial Cells / 대한해부학회지

ABSTRACT

Occludin is a cell adhesion molecule that is abundantly expressed in the kidney. However, the expression pattern in various renal epithelial cells is not well established. The purpose of this study was to determine the cellular localization along the tubular epithelial cells in the kidney. Kidneys from adult pigs crossbred of Yorkshire, Landrace and Duroc (three breeds) were processed for immunohistochemistry. Thiazide sensitive sodium chloride cotransporter (TSC), Na+-KATPase bat1, calbindinD28k, and H+-ATPase were used to identify the thick ascending limb, distal convoluted tubule, connecting tubule, and collecting duct, respectively. In the pig kidney, occludin was expressed in the apical domain of the tubular epithelial cells. The immunoreactivity of occludin was strongest in the collecting duct, and then gradually decreased in the connecting tubule, distal convoluted tubule, and thick ascending limb. Occludin expression was weak in the thin limbs of the loop of henle and in the proximal tubule in the pig kidney. These results suggest that occludin may be a major adhesion molecule in distal tubular epithelial cells and play a critical role in maintaining epithelial polarity of these nephron segments.