Abstract
Heightened pain sensitivity was frequently reported in opioid dependent patients on methadone maintenance therapy (MMT). This study investigated the influence of OPRM1 polymorphisms on pain sensitivity. Subjects were 148 Malay male opioid dependent patients receiving MMT. Their pain threshold (time elapsed when the subject started to perceive pain after immersion of hand), tolerance (time required for hand withdrawal), and intensity (0 - 100 visual analogue scale (VAS)) in response to cold pressor test (CPT) were measured at 0 hour (i.e. the time of the first CPT, and at 2, 4, 8, 12, and 24 hours after that. DNA was extracted from blood and subjected to PCR-genotyping. The differences of CPT responses between the OPRM1 polymorphisms were analysed using repeated measure analysis of variance (RM-ANOVA). There were no significant differences of pain responses (pain threshold, tolerance and intensity) between 118A > G and IVS2 + 691G > C polymorphisms of OPRM1 among opioid depedent subjects using genotype and allelic additive model, genotype dominant and recessive model, haplotypes and diplotypes analysis. The results suggest that the OPRM1 polymorphisms were not associated with differences in pain sensitivity. However, further investigations in larger numbers, other populations and pain models are required to confirm these findings.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
