Intravenously transplanted bone marrow stromal cells promote recovery of lower urinary tract function in rats with complete spinal cord injury.

OBJECTIVES: There is increasing evidence that intravenously injected neural progenitor cells promote recovery of bladder function in rodents, following contusive spinal cord injury through migrating into the injured spinal cord tissue and differentiating into central nervous system cells. The present study was aimed to clarify whether intravenously transplanted bone marrow stromal cells (BMSCs) could improve lower urinary tract (LUT) function in rats with spinal cord transection (SCT). METHODS: A total of 22 rats underwent experimentation in three groups, including group 1-sham operation, group 2 (BMSC)-SCT plus BrdU (5-bromo-2'-deoxyuridine) labeled BMSCs transplantation at day 9 after SCT, group 3-SCT control. All rats were investigated urodynamically on day 28 after transplantation. RESULTS: BMSCs identified by BrdU immunohistochemistry survived in the injured spinal cord and lumbar level 3-4 (L(3-4)). Voiding pressure, episodes of non-voiding contractions and residual urine volumes were significantly decreased in BMSC rats, compared with the controls. Bladder capacity was similar in both groups. In four out of eight BMSC rats and one out of seven controls, the tonic and bursting external urethral sphincter electromyographic activity were detected during cystometry. Silent periods during bursting were shorter and activity periods were longer in BMSC rats compared with sham rats. CONCLUSION: Intravenously transplanted BMSCs survived in the L(3-4) and had beneficial effects on the recovery of LUT function in the rats after SCT.