Objective: To investigate the protective effect of electroacupuncture (EA) at "Zusanli"(ST36)and "Weiwanxiashu"(EX-B3) on capillary function around the renal tubule and renal tubule structure in diabetic mice based on two-photon microscopy (TPM) imaging, so as to providing visualizable evidence for the regulatory effect of EA on diabetic renal vascular microcirculation.
Methods: Spontaneous type Ⅱ diabetes mellitus mice (db/db) were employed for this study. Twenty db/db mice were randomly divided into model group (n=10) and EA group (n=10), and 10 db/m mice used as the control group. EA was applied to bilateral ST36 and EX-B3 for 20 min/time, 6 times a week for 6 weeks. The body weight was recorded and the fasting blood glucose measured before and after the intervention. The urine production and water consumption of mice in each cage were recorded after EA. The renal in vivo imaging method based on TPM was established to display the morphological structure of renal tubules, and the mouse renal blood flow velocity was detected by injecting 500 kDa dextran-fluorescein into femoral vein after the intervention.
Results: Compared with the control group, the proportion of mice with decreased body mass in the model group was increased, accounting for 40%, while that in the control group was 0%; and fasting blood glucose, urine production and water consumption were significantly increased in the model group (P<0.001, P<0.000 1). A renal in vivo imaging method based on TPM was successfully established, which can be applied to quantitatively analyze the renal blood flow and renal tubular diameter of mice. Based on this method, the results showed that compared with the control group, the blood flow velocity of peritubular capillary in the model group was significantly decreased (P<0.000 1, P<0.001), renal tubular cells were slightly exfoliated and the diameter of renal tubular was significantly increased (P<0.000 1). Compared with the model group, EA reduced the body weight loss ratio from 40% to 0%, and significantly decreased the fasting blood glucose, urine production and water consumption (P<0.01, P<0.000 1, P<0.001), and the blood flow velocity of peritubular capillary in the EA group was significantly increased (P<0.001, P<0.05) and tubule dilatation significantly alleviated (P<0.0 1).
Conclusion: EA at ST36 and EX-B3 can ameliorate renal vascular microcirculation disorder to relieve the renal structure damage and improve renal function in diabetes mice.
目的：基于双光子显微镜建立肾脏活体成像方法，观察电针“足三里”“胃脘下俞”对糖尿病小鼠肾小管周围毛细血管功能、肾小管结构的保护作用，为电针调控糖尿病肾血管微循环提供动态可视化证据。方法：自发性Ⅱ型糖尿病动物模型C57BL/KS-db/db小鼠随机分为模型组和电针组，每组10只，同时将10只db/m同窝小鼠作为对照组。电针组小鼠取双侧“足三里”“胃脘下俞”行电针干预，20 min/次，每周治疗6次，共治疗6周。记录各组小鼠体质量；尾静脉取血测量空腹血糖；记录各组小鼠单日单笼排尿情况及饮水量。股静脉注射500 kDa 葡聚糖-荧光素，TPM肾脏活体成像法检测小鼠肾小管直径及其周围毛细血管血流速度。结果：与对照组比较，模型组体质量下降的小鼠占比升高，比例为40%，对照组则为0；模型组空腹血糖、排尿量、饮水量均显著升高(P<0.001，P<0.000 1)；肾小管周围毛细血管血流速度明显降低(P<0.000 1，P<0.001)；肾小管细胞可见脱落，肾小管直径增大(P<0.000 1)。与模型组比较，电针组体质量下降小鼠占比由40%降至0；空腹血糖、排尿情况及饮水量显著降低(P<0.01，P<0.000 1，P<0.001)；肾小管周围毛细血管血流速度显著升高(P<0.001，P<0.05)；肾小管直径缩小(P<0.01)。结论：电针“足三里”“胃脘下俞”可通过改善肾脏血管微循环障碍，提高肾小管周围毛细血管流速来缓解糖尿病引起的肾结构及功能损伤。.
Keywords: Diabetes; Electroacupuncture; Renal vascular microcirculation; Two-photon microscope.