可乐定透皮贴片的量效关系及生物利用度研究

Quantity-effect relationship and bioavailability of clonidine transdermal disk

可乐定贴片是新研制的透皮吸收控释膜剂，经过３Ｈ－标记的放射性同位素技术测定，家兔透皮吸收后，血药浓度在１６ｈ内维持在４．６３～９．２６ｎｍｏｌ·Ｌ－１，体内吸收情况与静脉滴注相仿，一次使用维持降压２４ｈ以上，其对数剂量与降压百分率呈良好的线性关系（ｒ＝０．９９０２，Ｐ＜０．０１）。并测得其ＥＤ５０为４０．１μｇ·ｋｇ－１，体内生物利用度为０．４４。

A transdermal disk of clonidine has recently been developed to release the drug at constant rate through skin.By teachnique of radioisotope(3H)in rabbits,it is found that its logarithmic dose and the percentage of reducing blood pressure(BP)is in linear relation-ship (r=0.9902,P<0.01).The plasmic concetration of clonidine is constant at 4.63～9.26 nmol·L-1 in 16 h.And the reducing BP effect by one piece maitains over 24h. It is detected that its ED50 40.1μg·kg-1 and bioavailability is 0.44.