Mulder G J, Groen K, Tijdens R B, Meijer D K
Xenobiotica. 1987 Jan;17(1):85-92. doi: 10.3109/00498258709047178.
Xamoterol has a phenolic hydroxyl group at which both sulphation and glucuronidation may occur. In the rat in vivo it is almost exclusively glucuronidated. In bile the glucuronide conjugate is the only metabolite of xamoterol. In urine equal amounts of the glucuronide conjugate and unchanged xamoterol are present, together with a small amount of the sulphate conjugate (approx. 1% of the dose). The t1/2 of excretion of the glucuronide in bile was the same as the t1/2 for excretion of unchanged xamoterol in urine. The t1/2 for urinary excretion of the glucuronide conjugate was longer than that for its biliary excretion. In the isolated perfused rat liver glucuronidation was also the almost exclusive metabolic pathway. The extraction ratio of xamoterol by the liver was approx. 0.15. Since xamoterol is a very water-soluble compound, and is almost exclusively glucuronidated in the rat, it is an excellent model substrate for investigations on the pharmacokinetics of glucuronidation in the rat in vivo and in isolated perfused organs.
醋丁洛尔有一个酚羟基，硫酸化和葡萄糖醛酸化均可在此发生。在大鼠体内，它几乎完全进行葡萄糖醛酸化。在胆汁中，葡萄糖醛酸结合物是醋丁洛尔唯一的代谢产物。在尿液中，葡萄糖醛酸结合物和未变化的醋丁洛尔含量相等，同时还有少量硫酸结合物（约占剂量的1%）。葡萄糖醛酸结合物在胆汁中的排泄半衰期与未变化的醋丁洛尔在尿液中的排泄半衰期相同。葡萄糖醛酸结合物在尿液中的排泄半衰期长于其在胆汁中的排泄半衰期。在离体灌注大鼠肝脏中，葡萄糖醛酸化也是几乎唯一的代谢途径。肝脏对醋丁洛尔的摄取率约为0.15。由于醋丁洛尔是一种水溶性很强的化合物，且在大鼠体内几乎完全进行葡萄糖醛酸化，它是研究大鼠体内和离体灌注器官中葡萄糖醛酸化药代动力学的极佳模型底物。
