Brief Reports
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World J Gastroenterol. Mar 28, 2005; 11(12): 1822-1824
Published online Mar 28, 2005. doi: 10.3748/wjg.v11.i12.1822
Stereoselective urinary excretion of S-(-)- and R-(+)-propranolol glucuronide following oral administration of RS-propranolol in Chinese Han subjects
Lian-Jun Luan, Qing Shao, Jian-Yin Ma, Su Zeng
Qing Shao, Su Zeng, Lain-Jun Luan, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310031, Zhejiang Province, China
Jian-Yin Ma, College, Zhejiang Ocean University, Zhousan 316000, Zhejiang Province, China
Author contributions: All authors contributed equally to the work.
Correspondence to: Professor Su Zeng, Department of Pharmaceutical Analysis and Drug Metabolism, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310031, Zhejiang Province, China. zengsu@zju.edu.cn
Telephone: +86-571-87217203 Fax: +86-571-87217086
Received: May 25, 2004
Revised: May 27, 2004
Accepted: June 17, 2004
Published online: March 28, 2005
Abstract

AIM: To study the stereoselectivity of phase II glucuronidation metabolism of side-chain propranolol in Chinese Han population.

METHODS: Sixteen adult Chinese Han volunteers with an average age of 20 years were given a single oral dose of 20 mg racemic propranolol. Human urine at indicated time after administration was collected and S-(-)-propranolol glucuronide and R-(+)-propranolol glucuronide were determined simultaneously by using RP-HPLC.

RESULTS: The mean values of k were 0.19±0.04 h-1 and 0.28±0.06 h-1, of t1/2 3.56±0.73 h and 2.45±0.50 h, of Tmax 2.21±0.45 and 1.75±0.33 h, and of Xu0-24 5.65±0.98 and 2.95±0.62 μmoL for S-(-)- and R-(+)-propranolol glucuronide, respectively. The cumulative excretion percentages in urine of doses were 14.7±2.46% and 7.68±1.60% for S-(-)- and R-(+)-propranolol glucuronide, respectively. The results showed the elimination rate constant k of S-(-)-propranolol glucuronide was less than that of R-(+)-propranolol glucuronide; and the elimination half-life (t1/2), Tmax and the cumulative excretion amount(Xu0-24) of R-(+)-propranolol glucuronide were significantly less than that of S-(-)-propranolol glucuronide.

CONCLUSION: The propranolol glucuronidation of the side-chain undergoes stereoselective excretion in Chinese Han population after an oral administration of racemic propranolol.

Keywords: Stereoselectivity; Excretion; Propranolol enantiomer; Glucuronidation