The changes of aquaporin 2 in the graft of acute rejection rat renal transplantation model.

Aim: To investigate the significance and changes of Aquaporin 2 (AQP2) in the rat renal graft of acute rejection (AR).
Methods: Wistar recipients of Spraque-Dawley or Wistar renal grafts were treated with cyclosporine (CsA). Renal grafts were harvested at various times after transplantation for analysis of the levels of AQP2 mRNA and protein of by RT-PCR and immunohistochemistry.
Results: The expression of AQP2 mRNA and protein in the acutely rejecting were grafts significantly decreased (P < 0.05) compared with the control group. But the expression of AQP2 mRNA and protein in the syngeneic grafts (sTX) versus the immunosuppression group (aTX+CsA) showed no difference compared with a control group (P > 0.05). Furthermore, at day 5 and day 7 after transplantation the expressions of AQP2 expression in the allogeneic group (aTX) were decreased significantly compared with day 3 after transplantation (P < 0.05). In addition, there was no remarkable difference at day 5 or 7 after transplantation.
Conclusion: AQP2 mRNA and protein expressions were down-regulated during renal transplant acute rejection, which had no relationship to the ischemia reperfusion injury and denervation damage. Furthermore, CsA administration after kidney transplantation blunted this down-regulation (P > 0.05).