Abst rac t : The 5-methyl and 14-ethoxy substituted analogues (compounds 2 4) of the 6 opioid receptor antagonist naltrindole showed similar selectivity when compared with the reference drug. Compound 2 was a 6 receptor antagonist in the mouse vas deferens preparation (MVD) exhibiting considerably higher selectivity ratios than naltrindole, while compound 4 was found to be a full and potent 8 r...

New mu-opioid receptor (MOR) agonists containing piperazine and homopiperazine moieties in the structures were synthesized and their affinities to and agonist potencies on MOR were evaluated. Among the synthesized compounds, 4-[4-(2-methoxyphenyl)piperazin-1-yl]-N,N-dimethyl-2,2-diphenylbutanamide (20 Aa) showed the highest affinity to the human MOR expressed in Chinese hamster ovary (CHO)-K1 c...

The report presented findings that the prescribing information of eight proprietary medicines containing codeine or other opioid-like compounds as published in Master Index of Medical Specialties (MIMS), a popular prescribing handbook in Hong Kong, did not include age-adjusted dosages for children and did not warn against their use in young children. As such, the authors warned medical practiti...

Endogenous opioid systems seem to have both neurodestructive and neuroprotective roles in CNS injury. Whereas mu and kappa 1 receptors appear to mediate neuroprotective actions, kappa 2 receptors may be involved in secondary injury responses. Among the endogenous opioids, dynorphin has marked neurotoxic effects when given intrathecally to rats; when administered in subinjury doses, dynorphin ex...

New racemic and chiral methyl 2-{[4-(4-chlorophenyl)-4-hydroxypiperidin-1-yl]methyl}-1-phenylcyclopropanecarboxylate derivatives were synthesized in order to obtain sigma ligands with increased affinity and selectivity compared to (+)-MPCB and haloperidol. The cis-(±)-7 racemic mixture showed a better binding affinity and selectivity than the (±)-8 trans isomers. Between the two cis enantiomers...

serotonin specific reuptake inhibitors (ssri) may induce antinociception however, the mechanism of this effect is not clear. ssrls increase 5-ht levels in neuronal synapses and facilitate serotonergic activity. in this study, therefore, the activity of para-chlorophenylalanine (pcpa), which reduces 5-ht release, and 5- hydroxy tryptophan (5-htp), a precursor of 5-ht, were examined on the antino...

The primate-exclusive MRGPRX2 G protein-coupled receptor (GPCR) has been suggested to modulate pain and itch. Despite putative peptide and small-molecule MRGPRX2 agonists, selective nanomolar-potency probes have not yet been reported. To identify a MRGPRX2 probe, we first screened 5,695 small molecules and found that many opioid compounds activated MRGPRX2, including (-)- and (+)-morphine, hydr...

BACKGROUND Artemisia macrocephala Jacquem (A. macrocephala), locally known as "Tarkha", is a perennial plant found abundantly in northern areas of Pakistan. It is widely used in traditional medicine to treat fever, pain, gastrointestinal disorders and diabetes. Till date, no published studies are available regarding the in-vivo antinociceptive potential of the crude extract and sub-fractions fr...

We have used single-channel patch-clamp recordings to study opiate receptor effects on freshly dissociated neurons from the rat amygdalohippocampal area (also called the posterior nucleus of the amygdala), an output nucleus of the amygdala implicated in appetitive behaviors. Dissociated cells included a distinct subpopulation that was 30-40 micrometer in diameter, multipolar or pyramidal in sha...

introduction: association between single-nucleotide polymorphisms (snps) in mu opioid receptor gene and drug addiction has been shown in various studies. here, we have evaluated the existence of polymorphisms in exon 3 of this gene in iranian population and investigated the possible association between these mutations and opioid addiction.  methods: 79 opioid-dependent subjects (55 males, 24 fe...