Several lines of evidence suggest that the N-methyl-D-aspartate receptor (NMDA) and nitric oxide (NO) systems are involved in morphine tolerance. Cyclooxygenase (COX) inhibitors may also play a role in morphine tolerance by interacting with both systems. In the present study, we examined the effects of the COX inhibitors N-(2-cyclohexyloxy-4-nitrophenyl) methanesulphonamide (NS-398, selective C...

BACKGROUND Inhibition of xanthine oxidase by allopurinol increases hypoxanthine and xanthine, which are converted to purines, including the inhibitory neuromodulator adenosine. AIM We aimed to investigate the antinociceptive effects of allopurinol in thermal and chemical pain models in mice and to evaluate its possible antinociceptive mechanism by using selective adenosine receptors A1, A2A a...

objective(s): nowadays, cox- 2 inhibitors such as valdecoxib are removed from the market because of their cardiovascular toxicity and their potential to increase the risk of strokes. in response to this, medicinal chemists have attempted to synthesize new classes of cox-2 inhibitors.   materials and methods: in this study, three novel analogues of thiazolidin-4-ones derivatives 2a-c were synthe...

Recently, the antinociceptive and anti-inflammatory efficacy of bee venom (BV, Apis mellifera) has been confirmed in rodent models of inflammation and arthritis. Interestingly, the antinociceptive and anti-inflammatory effect of whole BV can be reproduced by two water-soluble fractions of BV (>20 kDa:BVAF1 and<10 kDa: BVAF3). Based on these scientific findings, BV and its effective water-solubl...

Hypericum perforatum extract (St. John's wort, SJW), Harpagophytum procumbens extract (HPE) and Grape seed proanthocyanidin extract (GSPE) have a broad spectrum of biological activities including antidepressant, anti-inflammatory or anti-oxidant effects. The aim of this study was to clarify antinociceptive properties of SJW, HPE and GSPE in mice with mechanisms that might potentially underlie t...

BACKGROUND A long-acting analgesic may be particularly desirable in patients suffering from long-lasting pain. The aim of the study was to evaluate the antinociceptive effect of a novel nalbuphine preparation and to determine its duration of action. METHODS The antinociceptive effects of i.m. nalbuphine HCl in saline and nalbuphine base in sesame oil were evaluated in rats. The in vitro drug-...

Metanicotine [N-methyl-4-(3-pyridinyl)-3-butene-1-amine], a novel neuronal nicotinic agonist, was found to bind with high affinity (K(i) = 24 nM) to rat brain [(3)H]nicotine binding sites and it generalized to nicotine in a dose-dependent manner in the drug discrimination procedure. Metanicotine produced significant antinociceptive effects in mice and rats subjected to either acute thermal (tai...

Nociceptin/orphanin FQ peptide receptor (NOP) agonists produce antinociceptive effects in animal models after spinal administration and potentiate μ-opioid receptor (MOP)-mediated antinociception. This study determined the antinociceptive effects of spinally administered bifunctional NOP/MOP ligands and the antinociceptive functions of spinal NOP and MOP receptors in mice. Antinociceptive effec...

The anxiogenic and antinociceptive effects produced by glutamate N-methyl-D-aspartate receptor activation within the dorsal periaqueductal gray (dPAG) matter have been related to nitric oxide (NO) production, since injection of NO synthase (NOS) inhibitors reverses these effects. dPAG corticotropin-releasing factor receptor (CRFr) activation also induces anxiety-like behavior and antinociceptio...

in this study, we investigated the interactive effects of intraperitoneal (i.p.) injections of three different phosphodiesterase inhibitors (pdeis) on morphine-induced analgesia in mice using tail-flick method. subcutaneous administration of morphine (1, 3 and 6 mg/kg) caused significant antinociceptive effects in a dose dependent manner. administration of pentoxifylline (12.5, 25, 50 and 100 m...