- Poster presentation
- Open Access
UDP glucuronosyltransferase 2B7 single nucleotide polymorphism (rs7439366) influences heat pain response in human volunteers after i.v. morphine infusion
© Meissner et al. 2011
- Published: 1 March 2011
- Product Effect
- Pupil Diameter
- Homozygous Carrier
- Decrease Enzyme Activity
Morphine remains the most widely used intravenous opioid in the perioperative setting worldwide. Maintaining therapeutic CNS concentrations of many opioids is confounded by considerable variability in disposition. Recent findings indicate a role for the UGT2B7 expressed in the liver, for variability of substrate effects. This phenomenon is attributed to genetic and environmental factors. However, evidence for effect variation due to UGT2B7-mediated glucuronization of morphine in humans is lacking.
We tested the hypothesis that variations of morphine effects could be explained in part by genetic variation in the UGT2B7 gene by pupil diameter change and heat pain response in 35 healthy volunteers, who were given 0.2 mg/kg morphine i.v. over 2 hours. This abstract reports the results for the UGT2B7 (rs7439366) SNP on chromosome 4, coding for a histidine or a tyrosine at position 268, resulting in decreased enzyme activity.
While morphine effects might be influenced in part by UGT2B7 genotype, there is a differential effect on pupil contractility and heat pain response. This cannot be readily explained by drug or metabolite serum concentration and warrants further investigation, including different enzyme product effects on cerebral morphine levels.
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.