Pharmacokinetic evaluation of local drug delivery: the intratesticular and intrarenal administration of acenocoumarol in the rat.

According to theory, the regional increase in drug concentration during target organ directed drug delivery as compared with systemic drug delivery is related to the quotient of the clearance of the drug and the blood flow of the target organ. We investigated the steady-state pharmacokinetic disposition of S-acenocoumarol in plasma, liver, testis, and kidney following its administration (constant rate infusion by an osmotic minipump) directly into the testis or the kidney of rats. The effects of clearance induction (phenobarbitone treatment) on the disposition of the drug were also investigated. The results confirm the theory of target-directed drug delivery.