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...

We have compared the time course of the behavioral manifestations of opiate withdrawal to the in vivo activity of locus coeruleus (LC) neurons and to increases in the levels of G-proteins, adenylate cyclase, and cAMP-dependent protein kinase known to occur in the LC in opiate-dependent animals. Rats were given morphine by daily subcutaneous implantation of morphine pellets for 5 d. On the sixth...

Chronic morphine drives adaptations in synaptic transmission thought to underlie opiate dependence. Here we examine the role of micro-opioid receptor (MOR) trafficking in one of these adaptations, specifically, changes in GABA transmission in the ventral tegmental area (VTA). To address this question, we used a knock-in mouse, RMOR (for recycling MOR), in which genetic change in the MOR promote...

objective(s): evaluation of the sophora alopecuroides var. alopecuroides seed effects on morphine withdrawal syndrome in mice and determination of the alkaloid composition of the seed total extract. materials and methods:the effects of the seed total extract, alkaloid fraction and major compound matrine on the mice morphine withdrawal syndrome were compared to saline and methadone.mice were mad...

Previous pharmacological studies have implicated serotonergic brain systems in opiate withdrawal syndrome. Increased brain 5-HT release is associated with the development of physical dependence to morphine. Specific serotonin reuptake inhibitors, such as fluvoxamine and sertraline reduce the severity of naloxone precipitated opioid withdrawal syndrome. Other studies have shown that 5-HT system ...

The lateral hypothalamus (LH) is implicated in the behavioral actions of drugs of abuse, but the cellular and molecular basis of this role is unclear. Recent identification of neuropeptides localized in LH neurons has allowed for more specific studies of LH function. The LH-specific peptide orexin (hypocretin) has been shown to be important in arousal and sleep regulation. However, orexin cells...

Narcotic analgesics cause addiction by poorly understood mechanisms, involving mu opoid receptor (MOR). Previous cell culture studies have demonstrated significant basal, spontaneous MOR signaling activity, but its relevance to narcotic addiction remained unclear. In this study, we tested basal MOR-signaling activity in brain tissue from untreated and morphine-pretreated mice, in comparison to ...

INTRODUCTION Methadone has been used as a drug to detoxify opioid tolerance. Naloxane precipitated morphine withdrawal behaviours were attenuated by venlafaxine as an antidepressant. On the contrary, after detoxifying the opioids, spontaneous withdrawal syndrome may occur with pain sensitivity. Therefore the present study aimed to examine the effects of chronic methadone (70 mg/kg, in drinking ...

Introduction: Previous studies have suggested that plants Avena sativa, Hypericum perforatum, Passiflora incarnata and Lavandula officinalis can affect nervous system and reduce neural excitability and pain. The aim of this study was to evaluate the effect of a mixture of these four plant’s alcoholic extract on morphine withdrawal symptoms. Methods: Experiments were performed on four animal...

Background: Chronic administration of morphine cause physical dependence but the exact mechanism of this phenomenon remains unclear. The aim of this study is the assessment of systemic and intracerebroventricular (icv) administration of ramelteon (a melatonin receptor agonist) on morphine physical dependence. Methods: 88 adult male rats were divided into 2 major groups, namely “systematic” and ...