BACKGROUND Earlier observations show that development of persistent pain may be associated with the genetic variability in the gene encoding for the μ-opioid receptor 1, the OPRM1 A118G (rs1799971). The aim of this study was to investigate the association between OPRM1 genotype and subjective health complaints in patients with radicular pain and disc herniation. METHODS A prospective, 1-year ...

In a variety of species, development of attachment to a caregiver is crucial for infant survival and partly mediated by the endogenous opioids. Functional mu-opioid receptor gene polymorphisms are present in humans (OPRM1 A118G) and rhesus macaques (OPRM1 C77G). We hypothesized that rhesus infants carrying a gain-of-function OPRM1 77G allele would experience increased reward during maternal con...

The Asn40Asp variant (A118G) of the μ opioid receptor (OPRM1) gene is thought to contribute to the development and treatment of alcohol dependence. Employing positron emission tomography (PET), we first examined whether the single nucleotide polymorphism (SNP) modifies binding potential (BP(ND)) of the μ-selective ligand [(11)C]carfentanil in healthy control (Con) and 5-d abstinent alcohol-depe...

The mu-opioid receptor is encoded by the Oprm1 gene and contributes to mother-infant behaviors. Rodent dams lick male pups more than female pups in the anogenital region. This behavior is linked to stress responsivity in the offspring that may be mediated by epigenetic changes. We hypothesized that maternal behavior may affect DNA methylation levels of the Oprm1 gene and show sex differences. T...

BACKGROUND Polymorphisms in the μ-, δ- and κ-opioid receptor genes (OPRM1, OPRD1 and OPRK1) have been reported to be associated with substance (alcohol or drug) dependence. The influence of an individual gene on a disease trait should be more evident when analyzed in the context of gene-gene interactions. Thus, we assessed the joint effect of variants in these three opioid receptor genes on alc...

Transient global ischemia is a neuronal insult that induces delayed, selective death of hippocampal CA1 pyramidal neurons. A mechanism underlying ischemia-induced cell death is activation of the gene silencing transcription factor REST (repressor element-1 silencing transcription factor)/NRSF (neuron-restrictive silencing factor) and REST-dependent suppression of the AMPA receptor subunit GluR2...

INTRODUCTION Methadone is a full agonist of the opioid receptor mu 1 which is encoded by the OPRM1 gene. Sleep disorders were frequently reported by opioid-dependent patients during methadone maintenance therapy (MMT). It is possible, therefore, that genetic polymorphisms in OPRM1 influence sleep quality among patients on MMT. This study investigated the association of OPRM1 polymorphisms with ...

Chronic pain is associated with dysfunctional endogenous pain modulation, involving both central opioid and serotonergic (5-HT) signaling. Fibromyalgia (FM) is a chronic pain syndrome, characterized by widespread musculoskeletal pain and reduced exercise-induced hypoalgesia (EIH). In this study, we assessed the effects of 3 functional genetic polymorphisms on EIH in 130 patients with FM and 132...

Distribution of A118G single nucleotide polymorphism (SNP) in the mu-opioid receptor 1 gene (OPRM1) differs with ethnicity. We assessed the distribution of this SNP in Korean women with breast cancer and compared it with that in women of other ethnicities with breast cancer. Distribution of SNP genotypes was as follows: 49.8% for AG genotype, 40.6% for AA genotype, and 9.6% for GG genotype. Log...

The aim of this study was to investigate the effect of the μ-opioid receptor gene (OPRM1) A118G polymorphism on the requirement for post-operative fentanyl analgesia in patients undergoing radical gastrectomy. One hundred and twenty-eight gastric cancer patients scheduled to undergo radical gastrectomy under general anesthesia were enrolled in the study. Post-operative, patient-controlled intra...