脊髓损伤后逼尿肌细胞钙通道改变

目的 探讨脊髓损伤(SCI)后逼尿肌细胞钙通道改变及其与逼尿肌反射亢进(DH)的关系.方法 建立SD大鼠骶髓上损伤动物模型,进行逼尿肌条钙通道阻滞实验及逼尿肌细胞钙震荡激光共聚焦线性扫描.结果 相同前负荷下逼尿肌条的收缩频率SCI组(2.51±0.39)明显高于正常对照(C)组(1.95±0.58,P<0.05),滴加高浓度T型钙通道阻滞剂咪拉地尔后两者收缩频率降低至相同水平,滴加高浓度L型钙通道阻滞剂异搏定后两者收缩频率下降相同;逼尿肌细胞钙振荡频率SCI组(2.68±0.42)明显高于C组(1.87±0.48,P<0.05),滴加高浓度咪拉地尔后两者钙振荡频率降低至相同水平,滴加高浓度异搏定后两者振荡频率下降相同.结论 SCI后DH的发生与逼尿肌细胞T型钙通道性状改变密切相关.

The change of detrusor calcium channel after spinal cord injury

Objective To elucidate the change of detrusor calcium channel after spinal cord injury (SCI) and the relationship between the change of detrusor calcium channel and the detrusor hyperreflexia (DH). Methods Suprasacral cord injury animal models were made in female SD rats. Cystometry, blockage tests of calcium channel in isolated detrusor strips and line-scanning of detrusor Ca2+ oscillation by confocal laser scanning microscopy were performed. Results At the same preload,the detusor contraction frequency in SCI group (2.51±0.39) was quicker than the control group (1.95±0.58) (P< 0.05). The contraction frequency of two groups was decreased to the same level after adding high concentration of mibefradil ( blocker of T-type calcium channel), and the decrease in contraction frequency was same after adding high concentration of verapamil (blocker of L-type calcium channel). The Ca2+ oscillation frequency of detrusor ceils in SCI group (2.68±0.42) was quicker than in control group (1.87± 0.48) (P<0.05). When adding high concentration of mibefradil, the Ca2+ oscillation frequency of detrusor cells in the two groups was decreased to the same level, and when adding high concentration of verapamil, the decrease in the frequency was same. Conclusion The occurrence of DH after SCI is related to the changes of T-type calcium channel closely.