Improvement of bladder function and repair of axonal injury in rats with traumatic spinal cord injury via MAPK/ERK pathway by nerve growth factor / 西安交通大学学报(医学版)

ABSTRACT

【Objective】 To explore the effects of nerve growth factor （NGF） on bladder function and axon injury repair in rats with traumatic spinal cord injury （t-SCI） so as to explore its molecular mechanism. 【Methods】 Traumatic spinal cord injury model was constructed in 30 male SD rats by modified Allen’s beating method. The rats were randomly divided into sham-operation group， injury group and NGF group， with 10 rats in each group. We used the BBB score to observe the motor function of the rats’ hind limbs before and after the operation. The BL-420 biometer experimental system detected the urodynamics. Six anterior roots of the left lumbar taken from the distal end of the anastomosis were stained with toluidine blue， and the number of myelinated axons was counted. We used HE to stain rat bladder tissue， TUNEL to stain the rats’ severely injured spinal cord， and observed the spinal cord apoptosis rate. Western blotting was used to detect the protein expressions of Raf-1， p-MEK-2， MEK-2， ERK1/2， and p-ERK1/2 in spinal cord tissue. 【Results】 The BBB score results showed that there was no difference in the scores of the sham-operation group， the injury group and the NGF group before the operation. After the operation， the scores of the injury group and the NGF group were significantly lower than those in the sham-operation group （P0.05）. 【Conclusion】 NGF may hinder the conduction of MAPK/ERK pathway， thereby affecting the repair of axon damage and improving the bladder function of t-SCI rats.