OBJECTIVETo investigate the distributive path and proliferative rule of marrow mesenchymal stem cells (MSCs) in the rat transplanted via caudal vein from male rat to female rats model of chronic aristolochic acid nephropathy (CAAN).

METHODSCells taken from femoral bone marrow of male Wistar rats were made into single cell suspension, cultured, purified and identified as MSCs. MSCs were transplanted via caudal vein into 50 female Wistar CAAN model rats allocated in the test group, they were killed, 10 rats in a batch, at various time points (6 h, 48 h, 10 d, 30 d and 60 d after transplantation). Besides, 10 rats allocated in the control group were killed on the 30th day after received sham-transplantation. Kidney tissue of all rats was taken for detecting cells originated from the donors by fluorescence in situ hybridization test with FAM-labeled sex determining region of Y chromosome (SRY FISH) probe, and their number in SRY was counted using SRY PCR.

RESULTSMSCs were mainly distributed in the glomerular capillaries at the time points of 6 h and 48 h, but the number of MSCs in glomerular capillaries decreased and those in renal mesenchyma increased at the time points from 10 d to 60 d gradually, then tended to a steady state, meanwhile it showed a stable increasing trend in renal tubule. Cell colony of MSCs could be found in mesenchyma with a slowed down increasing between 30 d to 60 d, but the increasing in tubule was still steady.

CONCLUSIONMSCs originated from the donor can enter the kidney of acceptor and distribute from blood capillary to renal mesenchyma and tubule, and they can long time inhabit there and make propagation.