THE EFFECT OF SUBSTANCE P ON ISOLATED DETRUSOR
MUSCLE STRIPS FROM CHRONIC SPINAL CORD INJURED DOGS
Xie H, Liu G, Chen F, Liu B, Zhao H, Xu M, Xue H
Department of Peadiatric Urology, Xinhua Hospital,
Shanghai Second Medical University, Shanghai, China
Objective: The effect of
substance P (SP) on isolated detrusor muscle strips was investigated in
chronic spinal cord injured dogs.
Methods: 12 female dogs were
divided into 3 groups: normal, suprasacral and infrasacral group. The model
dogs were sacrificed 6 months after operation. Longitudinal detrusor muscle
strips were taken from the middle anterior bladder wall. The changes of
strips in spontaneous contraction include the frequency and amplitude, and
maximum contractile force were observed before and after exposed to 7.4×10-7M
SP.
Results: SP could potentiate
the amplitude of spontaneous contraction. The maximum contractile force
also increased significantly in all groups, and it listed as : suprasacral＞normal＞infrasacral
group(P＜0.05＝. SP did not affect the frequency of
spontaneous contraction.
Conclusion: The detrusor muscle
showed different sensibility to SP in different kind of neurogenic bladder
induced by chronic spinal cord injury. It suggested that SP may have a role
in pathological changes of neurogenic bladder.