Abstract
Objective : Glomerular expression of tensin was immunohistochemically studied in normal rat kidneys to determine whether tensin might be related to specific binding in individual glomerular cells.
Materials : Kidneys and cultured mesangial cells from Sprague-Dawlay rats were used.
Methods : Frozen sections of paraformaldehyde perfusion fixed kidneys were examined immunohistochemically using anti-tensin antibody. Cultured mesangial cells were examined at mRNA and protein levels by RT-PCR and immunoprecipitation.
Results : Immunofluorescence of normal rat kidneys displayed intense reactions for tensin along the basal aspects of proximal and distal tubular cells, and parietal epithelial cells of the Bowman's capsules. In glomeruli, positive reactions for tensin were detected only in the mesangial areas. Immuno-electron microscopy revealed positive reactions for tensin in the mesangial cell (MC) processes. RT-PCR and immunoprecipitation demonstrated mRNA and protein levels of tensin in the cultured rat MCs.
Conclusions : It appears that tensin is closely related to mesangial cell attachment to the surrounding extracellular matrix, and may play a role in the basic structural stabilizing system of the glomerular capillary architecture together with the glomerular basement membrane. Furthermore, tensin can act as a marker of rat MCs since the expression of tensin was detected only in MCs in the glomeruli.
