糖尿病大鼠逼尿肌细胞内游离钙离子浓度的变化

Changes of cytosol-free calcium concentration in single bladder smooth muscle cell from T2DM rats

目的观察2型糖尿病(T2DM)大鼠的逼尿肌细胞内游离钙离子浓度变化,为阐明糖尿病膀胱病变的发病机制提供依据。方法制备T2DM大鼠模型,在成模后4周和20周,以正常大鼠为对照,分离单个逼尿肌细胞并应用Fura-2／AM荧光探针负载,进行细胞内钙离子浓度的测定。结果发病初期,T2DM大鼠逼尿肌细胞内静息钙离子荧光比值(289．24±33．80)与正常对照组(276．85±57．90)比较,差异无统计学意义。在发病20周时,T2DM组大鼠逼尿肌细胞内钙离子荧光比值(545．94±79．28)比正常对照组(275．66±108．94)明显增高。结论细胞内钙超载参与了逼尿肌功能的损害的病理过程,但是发生相对较晚,可能在糖尿病膀胱发病的进展期起重要作用。

Objective To observe the changes of cytosol-free calcium concentration in single bladder smooth muscle ceU from T2DM rats in order to elucidate the pathogenesis of the damage in the T2DM rats＇ detrusor. Methods Rat T2DM model was developed and age-matched Wistar rats served as controls. Four and 20 weeks later, the effects of diabetes mellitus on intracellular calcium concentration were measured in single bladder smooth muscle cell in rats using the fluorescent calcium indicator dye Fura-2/AM at rest situation. Results The intracellular calcium concentration in single bladder smooth muscle cell in T2DM rats had no significant difference in the initial stage at rest situation in comparison to control group （289.24 ± 33.80 vs 276.85 ± 57.90）. However, at 20th week after onset, the intracellular calcium concentration in single bladder smooth muscle cell （545.94 ± 79.28） was significantly increased in T2DM rats as compared with that in control group （275.66 ± 108.94）. Conclusion Intracellular calcium overload occurred later than the dysbolism. Maybe intraeellular calcium overload is an important factor in the progression of diabetic eystopathy.