Kappa opioid receptor (KOR) desensitization was previously shown to follow agonist-dependent phosphorylation of serine 369 by G-protein receptor kinase (GRK) and beta-arrestin binding in transfected cells. To study the in vivo effects induced by phosphorylation of KOR(S369), C57Bl/6 mice were administered single or repeated doses of the KOR agonist, U50,488, and isolated brain glycoprotein was ...

Phytochemical analysis of Tanaecium bilabiatum leaf led to the isolation and identification salacinin C, daturadiol a mixture triterpenes, α-amyrin β-amyrin. Besides chemical analysis, methanol extract T. leaf, METBL was evaluated for analgesic, anti-diarrheal hypoglycemic potential in mice model. For analgesic activity test by tail immersion technique, significantly extended percent elongation...

The clinical usefulness of morphine for treatment of chronic pain is limited by development of tolerance. So many authors have proposed the co-administration of other drugs. This study was performed to evaluate the role of gabapentin on analgesic effect of morphine. Four groups of male rats (220-250 g) were examined for time latency using tail flick test: control, morphine (M), gabapentin (GB),...

BACKGROUND Opioids are the most widely used analgesics for the treatment of clinical pain. They produce their therapeutic effects by binding to mu-opioid receptors (MORs), which are 7 transmembrane domain (7TM) G-protein-coupled receptors (GPCRs), and inhibiting cellular activity. However, the analgesic efficacy of opioids is compromised by side-effects such as analgesic tolerance, dependence a...

Opioids are broad spectrum analgesics that may be beneficial to alleviate the intense perception of algesia in patients suffering with pain. They have been one of the most controversial analgesics, in part because of their potential for addiction. Opioids or any currently available analgesic will not provide effective analgesia for every patient with chronic neuropathic pain (NP), but overall o...

BACKGROUND Synergy between drugs manifests with increased potency and/or efficacy of the combination relative to either agonist given alone. Synergy is typically observed between drugs of different classes, as is the case with the alpha-adrenergic-opioid receptor synergy often observed in preclinical studies. However, rare studies report synergy between agonists of the same class. The current s...

The clinical usefulness of morphine for treatment of chronic pain is limited by development of tolerance. So many authors have proposed the co-administration of other drugs. This study was performed to evaluate the role of gabapentin on analgesic effect of morphine. Four groups of male rats (220-250 g) were examined for time latency using tail flick test: control, morphine (M), gabapentin (GB),...

Studies comparing morphine tolerance in males and females are rare, and all studies to date have utilized the rat. To generalize from findings with rats morphine tolerance was investigated in male and female mice using the tail-withdrawal test. Three and 7 days of systemic morphine injections produced significant but unequal rightward shifts in the morphine dose-response curve such that females...

with morphine together with subanalgesic doses of a second opiate did not develop tolerance to the morphine even after seven days of treatment. Although morphine is a favored choice for easing pain, a major drawback of its long-term use is the development of tolerance, which results in reduced analgesic effects upon long-term use. Morphine binds the opioid receptor (MOR), one member of the larg...

the goal of this study was to evaluate the effects of quercetin and acth injection on prevention of development of morphine tolerance and dependence in mice. in this study different groups of mice received morphine (40 mg/kg, i.p.) plus quercetin (5, 10, 25 mg/kg, ip), acth (1, 2.5, 5 iu/mice, i.p.), or combination of quercetin (5 mg/kg) and acth (1 iu/mice) once a day for four days. tolerance ...