胰岛素微粒剂的体外释药、小鼠体内分布与绝对生物利用度

采用放射免疫分析方法测定了胰岛素微粒剂的体外释药性 .用放射性标记技术制备了12 5Ⅰ 胰岛素微粒制剂 ,且以微粒剂中12 5Ⅰ 胰岛素的放射性计数为指标 ,研究了12 5Ⅰ 胰岛素在小鼠体内的生物利用度与组织分布 .研究表明 :微粒剂在不同pH值的磷酸盐缓冲液中 ,释药规律接近一级动力学方程 :ln(Q∞ -Q) =bt +A ,相关系数为rpH 2 5=- 0 .9398、rpH 7 0 =- 0 .9933,但更好地符合自拟释药方程 :Q =Q∞ bt/(1+bt) ,相关系数为rpH 2 5=- 0 .995 2、rpH 7.0 =- 0 .996 9.小鼠口服绝对生物利用度为 11.5 1%± 4.41% .12 5Ⅰ 胰岛素在小鼠脏器的同位素强度分布依次为肝、肾、心、肺、脾 .

Release Characteristics, Absolute Bioavailability and Distribution of the Insulin Microparticles(INS-MP)in Mice

The release characteristics of INS-MP were measured by the use of RIA. Using 125 Ⅰ labelled insulin,the preparation,absolute bioavailability and distribution of the 125 Ⅰinsulin microparticles in mice were studied according to the remaining activities of 125 Ⅰinsulin radioactivities.The studies indicated that the insulin-releasing profiles in vitro approached to the first order equation ln(Q ∞-Q)=bt+A,r pH 2.5 = -0.939 8 、r pH 7.0 =-0.993 3,and more fitted to the selfdraft equation Q=Q ∞bt/(1+bt),r pH 2.5 = -0.995 2 、r pH 7.0 =-0.996 9.The absolute bioavailability was 11.51%±4.41%,the distribution sequence of isotope intensity of 125 Ⅰ labelled insulin in mice′tissues was as follows:liver,kidney,heart,lungs and spleen.