Molecular detection of heparan sulfate proteoglycan mRNA in rat kidney during calcium oxalate nephrolithiasis.

The present study used reverse transcription (RT)-PCR to examine heparan sulfate proteoglycan (HSPG) mRNA expression in rat kidneys. Total mRNA in kidney was isolated and converted to cDNA. To confirm the exact expression level of HSPG mRNA, quantitative competitive (QC)-PCR was performed for each sample. PCR products were resolved by electrophoresis on 1.5% agarose gel and visualized with ethidium bromide. Fragment intensity and area were measured using an image analyzer. In QC-PCR, target DNA and competitive DNA were expressed, using gene-specific primer for HSPG mRNA, as 506- and 345-bp bands, respectively. The level of HSPG mRNA expression apparently increased in the nephrolithic rat kidney. Immunohistochemical study revealed that increased production of heparan sulfate was detected in both distal and proximal tubules during nephrolithiasis. These findings suggest that increased expression of HSPG may play a significant role during calcium oxalate stone formation.