胰岛素穴位缓释注射对SD大鼠不同时间降糖效应的影响

摘要

目的：观察胰岛素结合PVP缓释剂穴位注射对SD大鼠不同时间血糖值、血清胰岛素含量变化并分析其相关性。方法将144只SD雄性大鼠随机分为A组(单纯胰岛素穴注组)、B组(胰岛素穴注缓释组)和C组(对照组)。各组以40%葡萄糖(剂量为2.2 g/kg)灌胃1 h后,A组和B组进行足三里穴位注射,C组不予处理。3组分别于穴位注射后0.5 h、3 h、6 h、8 h、10 h和24 h 6个时间点测定大鼠血糖值及血清胰岛素含量(C组按相应时点取血测定)；同时在穴位注射后3 h、10 h、24 h 3个时间点采用光镜观察各组大鼠足三里穴区组织刺激反应。结果 A组和B组降糖率均在穴位注射后3 h到达高峰后逐渐下降。A组在穴位注射后6 h降糖作用趋于稳定,B组在穴位注射后10 h趋于稳定,且B组在穴位注射后6 h与8 h的降糖作用明显优于A组(P＜0.01)。A组血清胰岛素在穴位注射后3 h到达高峰(P＜0.05),至6 h趋于稳定。B组在穴位注射后0.5 h、3 h、6 h、8 h 4个时间点血清胰岛素含量均显著低于A组(P＜0.05)。大鼠血清胰岛素含量与降糖率相关性分析显示,A组存在显著正相关(P＜0.01),B组存在低度正相关(P＜0.05)。穴位注射后3h、8 h、24 h 3个时间点A组和B组大鼠足三里穴区周围肌纤维组织横纹清晰、结构完整,无明显变性、坏死和炎性反应,与C组比较无明显病理变化。结论 PVP缓释剂可减缓胰岛素在大鼠足三里穴区的吸收速率,同时延长了胰岛素降糖效应持续时间,而且显示血清胰岛素含量与降糖效应的相关性降低,提示穴位注射缓释技术可以延长药物穴位注射效应。%Objective To observe blood glucose values and serum insulin levels at different times after acupoint injection of insulin with PVP as a sustained release agent and analyze the correlation between them in SD Rats.Methods One hundred and forty-four male SD rats were randomized into groups A (acupoint injection of insulin alone), B (acupoint injection of sustained-release insulin) and C (control). At one hour after every group received an oral gavage of 40% glucose solution (2.2 g/kg), groups A and B were given point Zusanli injection and group C was not treated. In the three groups of rats, blood glucose values and serum insulin levels were measured at six time points: 0.5, 3, 6, 8, 10 and 24 hours after acupoint injection (in group C at the corresponding time points). In every group, the reaction of Point Zusanli region to the stimulation was observed by optical microscopy in at three time points: 3, 10 and 24 hours after acupoint injection.Results The glucose-lowering rate reached its peak at 3 hours after acupoint injection and then declined in groups A and B. The hypoglycemic effect tended to be stable at 6 hours after acupoint injection in group A and at 10 hours after acupoint injection in group B. The hypoglycemic effect was better in group B than in group A at 6 and 8 hours after acupoint injection (P<0.01). In group A, serum insulin reached its peak at 3 hours and tended to be stable at 6 hours after acupoint injection (P<0.05). Serum insulin levels were significantly lower in group B than in group A at four time pints: 0.5, 3, 6 and 8 hours after acupoint injection (P<0.05). An analysis of the correlation between rat serum insulin levels and the glucose-lowering rate showed a significant positive correlation in group A (P<0.01) and a low positive correlation in group B (P<0.05). In groups A and B of rats, clear stripes and complete structure of muscle fibers were seen with no obvious degeneration, necrosis and inflammatory reaction around point Zusanli at three time points: 3, 8 and 24 hours after acupoint injection; there were no obvious pathological changes compared with group C.Conclusions PVP as a sustained release agent can slow down the absorption rate of insulin in rat point Zusanli region. Meanwhile, it prolongs the continuous time of the hypoglycemic effect of insulin. There is a low correlation between serum insulin levels and the hypoglycemic effect, suggesting that acupoint injection with a sustained release agent can prolong the effect of acupoint injection of medicine.