Immunohistochemical localization of napsin and its potential role in protein catabolism in renal proximal tubules.

摘要: In a previous in situ hybridization study, we demonstrated the mRNA expression of napsin, an aspartic protease pepsin family, kidney, lung, and lymphoid organs mice. However, findings on cellular localization napsin at protein level are controversial, no information subcellular is available. The present immunohistochemical study revealed mice rats, also analyzed influences chemical-induced proteinuria renal this enzyme rats. Immunohistochemistry using polyclonal antibody against mouse showed that immunoreactivity was noticeable lysosomes proximal tubule cells lamellar bodies pulmonary type II alveolar cells. found macrophages surface I cells; immunoreactivities these may be due to uptake adhesion secreted from cells, since they did not express mRNA. Conversely, for undetectable B lymphocytes with intense expression. puromycin- or doxorubicin-induced proteinuria, markedly elevated tubules, showing characteristic distribution patterns. Immunostaining kidneys congested enlarged lysosomes, called absorption droplets. These results indicate functions as lysosomal involved catabolism tubules.