氮酮促进洛美沙星仔猪皮肤吸收机理的研究

选用10～12日龄同品种仔猪,随机分组,于仔猪腹部皮肤涂搽含氮酮的洛美沙星透皮吸收剂, 分别于涂药前、涂药后2、4、6、12、24、48和72 h 在体取皮,应用透射电镜观察皮肤表皮结构变化,探讨氮酮促进洛美沙星透皮吸收的作用机理.结果表明,氮酮通过以下途径促进药物透皮吸收:(1)作用于表皮角质层细胞间脂质,使角质层变得疏松,细胞间距增大,外角质层细胞易于脱落,降低了皮肤对药物的屏障作用;(2)氮酮进入角质细胞内,与细胞内基质相作用,引起基底角质层肿胀,增加了角质细胞水化程度和药物存储空间.研究还发现,氮酮在体对仔猪皮肤的作用可维持72 h 以上;由氮酮引起皮肤结构的改变是一非损伤可复性过程.

Mechanism of the enhancement effect of laurocapram on the transdermal absorption of lomefloxacin through piglet's skin

The present study explores the effect of chemical penetration enhancer-laurocapram in the percutaneous absorption preparation of lomefloxacin on the in vivo ultrastructural changes in epidermis of piglet as observed by transmission electron microscopy (TEM). The results demonstrated that laurocapram disrupts the highly ordered lipid structure of stratum corneum (SC) and makes the structure of SC loose, which causes the outermost cell of SC easy to exfoliate and decreases the barrier function of skin for the transdermal absorption of drug;Meanwhile, laurocapram penetrating into the intracellular matrix of SC cells fluidizes the filaggrin matrix protein and swells the dermal SC, which could increase the free volume of drug and water content in the SC. The study also discovered that the barrier structure of SC at 72 hours after medication is still in the state of recovery, and that the change of epidermis caused by laurocapram is a non-damnifing and reversible course.