The neuropeptide orphanin FQ/nociceptin (OFQ/N) has been shown to counteract several effects of endogenous and exogenous opioids, and it has been proposed as an opioid-modulating agent involved in the development of morphine tolerance and dependence. However, conflicting results have been obtained from animal models using different protocols to induce morphine tolerance. Here, we report that bo...

AIM This research was carried out to compare magnesium sulfate (MgSO4) with isotonic saline in terms of pain control after herniorrhaphy. PATIENTS & METHODS A randomized double-blind study, in which the patients were blind to all. A total of 100 patients who were candidates of herniorrhaphy were randomized into two groups: experimental and control (50 patients in each). Anesthesia was induced...

Repeated administration of morphine is associated with the development of tolerance, yet the mechanism underlying this phenomenon is still poorly understood. Recent evidence implicating glycogen synthase kinase 3 (GSK3) in opioid receptor signaling pathways has prompted us to investigate its role in morphine tolerance. Administration of 10 mg/kg morphine i.p. to Wistar rats twice daily for 8 da...

BACKGROUND Morphine and clonidine show synergy or antagonism inhibiting gastrointestinal transit depending on their proportion and level of effect. Their interaction during morphine tolerance and intestinal inflammation were assessed. METHODS Gastrointestinal transit in mice was evaluated with charcoal and antitransit effects expressed as percent mean values +/- SEM. Tolerance was induced wit...

Nalbuphine hydrochloride is a relatively new agonist-antagonist drug structurally related to the potent narcotic, oxymorphone (Numorphan®), and the potent narcotic antagonist, naloxone (Narcan®). (Figure 1.) Nalbuphine has a potency equivalent to morphine sulphate and meperidine (10 mg morphine sulphate and 75 mg meperidine being equivalent to 20 mg nalbuphine), 1 with an abuse potential which ...

There are controversial reports on the effect of diabetes on the pain threshold. We used male Wistar rats to see the effect of streptozotocin induced diabetes on the tail flick, vocalisation and vocalisation after discharge responses. These represent the spinal, lower brain stem and hypothalamic responses respectively. The effect of morphine in these parameters was studied for both the control ...

backgrounds and aims: cinnamomum zeylanicum is a medicinal herb used in iranian traditional medicine as an analgesic spice, which its analgesic effect has been experimentally confirmed. thus, this study was conducted to compare the antinociceptive effect of cinnamon essential oil (ceo) with those of morphine and diclofenac in mice. materials and methods: 80 male albino mice were selected and ra...

6beta-Naltrexol is the major metabolite of the opioid receptor antagonist, naltrexone, in humans. However, there are no functional studies of 6beta-naltrexol in primates. The aim of this study was to compare the in vitro and in vivo potencies of naltrexone and 6beta-naltrexol in rhesus monkeys. Affinity and potency were determined using radioligand displacement and stimulation of 5'-O-(3-[(35)S...

Central or systemic administration of agonists directed at the mu or delta opiate receptors generally produce a greater degree of analgesia in males than in females. To date, most studies examining sex-based differences in opioid analgesia have used acute noxious stimuli (i.e., tail-flick and hot plate test); thus the potential dimorphic response of centrally acting opiates in the alleviation o...