The tolerance and dependence after chronic medication with morphine are thought to be representative models for studying the plasticity, including the remodeling of neuronal networks. To test the hypothesis that changes in neuronal plasticity observed in opioid tolerance or dependence are derived from increased activity of the anti-opioid nociceptin system, the effects of chronic treatments wit...

BACKGROUND Chronic use of opioids usually results in physical dependence. The underlying mechanisms for this dependence are still being evaluated. Transient receptor potential vanilloid type 1 (TRPV1) are important receptors of pain perception. Their role during opioid dependence has not been studied well. The aim of this study was to evaluate the effect of morphine-dependence on the expression...

the mechanisms of drug dependence and rewarding properties of opiates are not exactly known and several neurotransmitters seem to be involved. it is possible that the rennin-angiotensin system could interact with the opioid system, since it has been shown that angiotensin ii(ang) and ace inhibitors have analgesic, anticonvulsant and antidepression effects and in some cases they could antagonize...

introduction: morphine withdrawal syndrome is mediated via several central and peripheral neurological pathways. in the present study we investigated the role of n-methyl-d aspartic acid (nmda) glutamate receptor on naloxone-induced withdrawal syndrome in morphine-conditioned mice. materials and methods: we designed two separate experiments. in experiment one, 30 male nmri mice were divided int...

Drug abuse and dependence have progressively become a dramatic problem in human societies. Since the exact mechanism(s) of the effect of related drugs in the brain has not been explored, therefore, this problem has not been resolved yet. Several lines of evidence indicated that nitric oxide (NO) plays an important role in the process of drug dependence. The role of NO within the different regio...

The clinical use of morphine to reduce pain is limited because of its drug tolerance, dependence and addiction. In the present study, the tree shrews (Tupaia belangeri chinensis) developed morphine tolerance and chronic morphine dependence by morphine injections with increasing doses (5, 10, 15, 20 mg/kg body weight for 7 days). Meanwhile, the naloxone (1.25 mg/kg body weight)-induced condition...

Tolerance and dependence are two main problems that have limited morphine administration. There are several reports on the effect of some medicinal plants on morphine-induced tolerance and dependence. In this study we investigated the effect of Ferula persica (FP) extract on modulation of withdrawal syndrome sign (WSS). For this purpose, male Albino mice (25-30 g, n=30) were used. Morphine was ...

Tolerance and dependence are two main problems that have limited morphine administration. There are several reports on the effect of some medicinal plants on morphine-induced tolerance and dependence. In this study we investigated the effect of Ferula persica (FP) extract on modulation of withdrawal syndrome sign (WSS). For this purpose, male Albino mice (25-30 g, n=30) were used. Morphine was ...

BACKGROUND Repeated morphine treatment has been shown to induce transient receptor potential vanilloid type 1 (TRPV1) expression in the spinal cord, dorsal root ganglion (DRG), and sciatic nerve of a rat model. Increased TRPV1 expression may therefore play a role in morphine tolerance. In this study, we evaluated the hypothesis that blockage of TRPV1 may be useful as an adjunctive pain manageme...

Acute morphine withdrawal is considered to be the physical manifestation of dependence, emerging when morphine administration is stopped or after the administration of an opiate antagonist, such as naloxone. Gabapentin, which is an antiepileptic, agent, enhances the analgesic effect of morphine in healthy volunteers, but its effect on morphine dependence and withdrawal signs has not determined ...