胰岛素柔性脂质体经小鼠皮肤给药的降血糖作用

 目的研究胰岛素柔性脂质体的制备及其对正常小鼠经皮给药的降血糖效果。方法以逆相蒸发-探针式超声法制备胰岛素柔性脂质体，对其形态、大小和包封率进行测定；以0.60U·cm^-2的剂量，将其非封闭性涂布于小鼠皮肤，用酶-苯酚法测定小鼠血糖，并与胰岛素普通脂质体、胰岛素溶液比较。结果胰岛素普通脂质体和柔性脂质体的粒径分别为(61.82±6.89)，(74.O±7.65)nm，多分散性指数分别为(50.61±6.32)%，（14.62±4.01）%，包封率分别为(31.61±1.23)%，(35.35±3.49)%)n=3）。胰岛素柔性脂质体在1h内降糖百分率为(21.42±10.19)%，5h时达到（61.48士8.97）%，维持降糖时间18h。胰岛素普通脂质体和胰岛素溶液几乎没有降糖作用，与给予生理盐水对照组相当。结论柔性脂质体有较强的皮肤穿透作用，可能成为大分子药物经皮渗透的有效载体。

Studies on hypoglycemic effects of insulin-flexible liposomes after transdermal delivery in mice

OBJECTIVE The study was undertaken to prepare the flexible lecithin liposomes contzurung insulin and to investigate the transdermal enhancing effect of flexible liposomes on insulin. METHODS Both the conventional liposomes and flexible liposomes were prepared by reverse-phase evaporation and then sonication.1he liposomal entrapment efficiency was determined by column chromatography.When the liposomes were non-occlusively applied onto the abdominal skin at the dose of O.60 u·cm^-2in vivo,the hypoglycemic effect was investigated. RESULTS The particle sizes of the conventional and flexible liposomes were(61.82±6.89)nm and (74.0±7.65)nm with polydispersity index of (50.61±6.32)%and(14.62±4.01)%,respectively. The entrapment efiiciencies of the conventional and flexible liposomes were(31.61±1.23)% and(35.35±3.49)%(n=3),respectively. In vivo hypoglycemic study showed the drop percentages of blood glucose by flexible liposomes were(21.42±10.19)% at 1h,(61.48±8.97)% at 5 hand remained less than 50% within 18h, respectively.The conventional liposomes,insulin solution and saline had no hypoglycemic efirect.CONCLUSION The flexible liposomes may becomea promising canier for the transdermal delivery of hydrophilic proteins.