Expression of UDP-Glucuronosyltransferases (UGTs) 2B7 and 1A6 in the Human Brain and Identification of 5-Hydroxytryptamine as a Substrate

doi:10.1006/abbi.1999.1155

Archives of Biochemistry and Biophysics

Volume 365, Issue 1, 1 May 1999, Pages 156-162

https://doi.org/10.1006/abbi.1999.1155 Get rights and content

Abstract

The extrahepatic expression of UDP-glucuronosyltransferases (UGTs) is important in the detoxification of a number of endogenous and exogenous compounds, including 5-hydroxytryptamine and morphine. Studies were designed to investigate the extrahepatic expression of human UGTs using RT-PCR techniques and to determine the UGTs involved in the glucuronidation of 5-hydroxytryptamine. Human UGT2B7 expression was found in the human liver, kidney, pancreas, and brain, while UGT1A6 expression is found in the liver, kidney, and brain. This is the first observation of UGTs present in the human central nervous system. Using glucuronidation assays, a significant amount of 5-hydroxytryptamine glucuronide was found to be catalyzed by UGT1A6. These studies suggest that UGT2B7 may play an important role in the overall contribution of morphine analgesia by serving to generate the potent morphine-6-O-glucuronidein situ.UGT1A6 could play an important role in the glucuronidation of 5-hydroxytryptaminein vivo,therefore terminating the actions of the neurotransmitter.

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^☆: This research was supported by NIH Grant GM26221.

^☆☆: Kosterlita, H. W.

²: To whom correspondence should be addressed at Department of Pharmacology, 2-452 BSB, University of Iowa, Iowa City, IA 52242. Fax: (319) 335-8930.

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Regular ArticleExpression of UDP-Glucuronosyltransferases (UGTs) 2B7 and 1A6 in the Human Brain and Identification of 5-Hydroxytryptamine as a Substrate☆,☆☆

Abstract

J. Biol. Chem.

J. Biol. Chem.

Biochem. Biophys. Res. Commun.

Biochem. Biophys. Res. Commun.

Biochem. Biophys. Res. Commun.

J. Biol. Chem.

FEBS Lett.

J. Biol. Chem.

J. Biol. Chem.

J Biol. Chem.

Arch. Biochem. Biophys.

Neuropharmacology

Neurosci. Lett.

Pain

Arch. Biochem. Biophys.

J. Biol. Chem.

Anal. Biochem.

Life Sci.

Eur. J. Pharmacol.

Biochem. Pharmacol.

J. Biol. Chem.

Glucuronidation of Drugs and Other Compounds

Pharmacogenetics

J. Biochem.

Drug Metab. Dispos.

Drug Metab. Dispos.

Arch. Biochem. Biophys.

DNA Cell Biol.

J. Pharmacol. Exp. Ther.

Regular Article
Expression of UDP-Glucuronosyltransferases (UGTs) 2B7 and 1A6 in the Human Brain and Identification of 5-Hydroxytryptamine as a Substrate☆,☆☆