INTRODUCTION Opioid analgesia can be explored with quantitative sensory testing, but most investigations have used models of phasic pain, and such brief stimuli may be limited in the ability to faithfully simulate natural and clinical painful experiences. Therefore, identification of appropriate experimental pain models is critical for our understanding of opioid effects with the potential to i...

P-glycoprotein (P-gp), one of the important drug-efflux pumps, is known to affect pharmacokinetics and pharmacodynamics of P-gp substrate drugs. We have previously reported that intestinal P-gp expression levels are transiently decreased in streptozotocin (STZ)-induced type 1 diabetic mouse model. Herein, we examined the analgesic effects of orally administered morphine and its pharmacokinetic ...

Background: Morphine and lidocaine are known to influence the perception of pain. The present study sought to determine the influence of local administration of morphine on lidocaine-induced analgesia in morphine non-dependent (MND), morphine dependent (MD) and morphine withdrawal (MW) animals. Methods: Adult male Wistar rats were divided into four groups: Control, MND, MD and MW rats. Lidocai...

BACKGROUND Morphine and lidocaine are known to influence the perception of pain. The present study sought to determine the influence of local administration of morphine on lidocaine-induced analgesia in morphine non-dependent (MND), morphine dependent (MD) and morphine withdrawal (MW) animals. METHODS Adult male Wistar rats were divided into four groups: Control, MND, MD and MW rats. Lidocain...

BACKGROUND The aim of this study was to investigate the role of chemokine (C-X-C motif) ligand 13 (CXCL13) in morphine tolerance in rats with cancer-induced bone pain (CIBP). MATERIAL AND METHODS We established a rat CIBP model and a rat CIBP-morphine tolerance (BM) model. BM rats were intrathecally administered rmCXCL13, neutralizing anti-CXCL13, and normal saline, while the control group rats...

Introduction: Previously, we demonstrated that i.p. injection of aqueous extract prepared from aerial parts of Drosera Spatulata (Droseraceae) can induced remarkable analgesia in both phases of formalin test in rats. Because, analgesia induced in acute phase of formalin test mainly mediated by activation of central analgesic mechanisms and also paragigantocellularis (PGi) nucleus is part of bra...

Evaluation of mRNA Expression Calcitonin Gene-Dependent Peptide (CGRP) and Rat (rCT) in the Periaqueductal Gray Area (PAG) Diabetic Rats Formalin Test

CI-1021 ([(2-benzofuran)-CH(2)OCO]-(R)-alpha-MeTrp-(S)-NHCH(CH (3))Ph) is a selective and competitive neurokinin-1 (NK(1)) receptor antagonist. This study examines its activity in animal models of inflammatory and neuropathic pain. In mice, CI-1021 (1-30 mg/kg, s.c.) dose dependently blocked the development of the late phase of the formalin response with a minimum effective dose (MED) of 3 mg/k...

OBJECTIVE The genus Marrubium is used for treatment of joint pain, gout, stomach-ache and colic in Iranian Traditional Medicine. Marrubium astracanicum Jacq. (M. astracanicum) is a native species in the flora of Iran. The aim of this study was to evaluate the antinociceptive properties of various extracts of aerial parts of M. astracanicum. MATERIALS AND METHODS Antinociceptive activities of ...

BACKGROUND AND AIMS Chronic opioid analgesia has the debilitating side-effect of constipation in human patients. The major aims of this study were to: 1) characterize the opioid-specific antagonism of morphine-induced inhibition of electrically driven contraction of the small intestine of mice, rats, and guinea pigs; and 2) test if the oral delivery of small milk-derived opioid antagonist pepti...