Effect of castration on renal glycosaminoglycans and their urinary excretion in male and female rats with chronic renal failure

Glycosaminoglycans (GAGs) participate in a variety of processes in the kidney,and evidence suggests that gender-related hormones participate in renalfunction. The aim of this study was to analyze the relationship of GAGs, gender,and proteinuria in male and female rats with chronic renal failure (CRF). GAGswere analyzed in total kidney tissue and 24-h urine of castrated (c), male (M),and female (F) Wistar control (C) rats (CM, CMc, CF, CFc) and after 30 days ofCRF induced by 5/6 nephrectomy (CRFM, CRFMc, CRFF, CRFFc). Total GAGquantification and composition were determined using agarose and polyacrylamidegel electrophoresis, respectively. Renal GAGs were higher in CF compared to CM.CRFM presented an increase in renal GAGs, heparan sulfate (HS), and proteinuria,while castration reduced these parameters. However, CRFF and CRFFc groups showeda decrease in renal GAGs concomitant with an increase in proteinuria. Ourresults suggest that, in CRFM, sex hormones quantitatively alter GAGs, mainlyHS, and possibly the glomerular filtration barrier, leading to proteinuria. Thelack of this response in CRFMc, where HS did not increase, corroborates thistheory. This pattern was not observed in females. Further studies of CRF areneeded to clarify gender-dependent differences in HS synthesis.