EFFECT OF 3-MA ON THE NEUROGENIC URINARY BLADDER AFTER SPINAL CORD INJURY IN RATS BY INHIBITING THE AUTOPHAGY REACTION OF URINARY BLADDER DETRUSOR MUSCLE CELLS

Xin Cui^#, Chunsong Jia^#, Hao Yan, Zhenhua Shang, Tianying Xing, Tongwen Ou^*

Department of Urology, Xuanwu Hospital, Capital Medical University, Beijing 100053, PR China

Objective: To analyze the effects of 3-methyladenine (3-MA) on the neurogenic bladder after spinal cord injury (SCI) in rats via the inhabitation of the autophagic response of bladder detrusor muscle cells. 

Methods: Fifty, 8-week-old male Sprague-Dawley (SD) rats were selected and prepared by spinal cord transection to generate a neurogenic bladder model after SCI. The hindlimb motor function of the rats was evaluated 3, 9, and 18 d after modeling using the BB behavior score. The levels of autophagy-associated protein microtubule-associated protein 1 light chain 3 type II (LC3-Ⅱ) and basic myelin sheath protein (MBP) were detected. The effects of 3-MA on the neurogenic bladder after SCI, via the inhibition of the autophagic response of bladder detrusor muscle cells, were analyzed. 

Results: The BBB scores of both the model group and the 3-MA group were lower than those of the sham operation group, at each time point, and the BBB scores for the 3-MA group were higher than those for the model group, the difference is statistically significant (P<0.05). At each time point, the LC3-II level of rats in the model group was significantly higher than that in the sham operation group, and the LC3-Ⅱ level of the 3-MA group at each time point was significantly lower than that of the model group (P<0.05). In the model group, 3 and 18 d after the operation, the MBP levels in the model group were significantly lower than those in the sham operation group. The MBP levels in the 3-MA group, 3 and 18d after the operation, were significantly higher than those in the model group (P<0.05). 

Conclusion: An obvious autophagy reaction occurs in the detrusor myocytes in rats with neurogenic bladder after SCI, and the autophagy inhibitor 3-MA can reduce the MBP loss and inhibit bladder detrusor in rats by inhibiting the autophagy reaction of the bladder detrusor muscle cells.