Previous studies have reported that morphine exerts its effects in part through the release of nitric oxide (NO). It has been pustulated that drug sensitization is a major cause of relapse to drug use in addicts. In the present study the effects of intra-accumbal injections of L-arginine, the NO precursor and L-NAME, the NOS inhibitor on the morphine sensitization in Wistar rats (250-300 g) wer...

Introduction: We investigated the role of ATP-sensitive potassium channels and L-type calcium channels in morphine-induced hyperalgesia after nociceptive sensitization. Methods: We used a hotplate apparatus to assess pain behavior in male NMRI mice. Nociceptive sensitization was induced by three days injection of morphine and five days of drug free. On day 9 of the schedule, pain behavior te...

introduction: we investigated the role of atp-sensitive potassium channels and l-type calcium channels in morphine-induced hyperalgesia after nociceptive sensitization. methods: we used a hotplate apparatus to assess pain behavior in male nmri mice. nociceptive sensitization was induced by three days injection of morphine and five days of drug free. on day 9 of the schedule, pain behavior test ...

Background: The amygdala is one of the nerve centers involved in drug reward. It is suggested that the central nucleus of the amygdala (CeA) is involved in morphine dependency. The CeA gamma-aminobutyric acid-ergic (GABAergic) system is a mediator of morphine rewarding effects. In this research, the effects of stimulation or inhibition of CeA GABA type B (GABAB) receptors on sensitization acqui...

Previous studies have reported that morphine exerts its effects in part through the release of nitric oxide (NO). It has been pustulated that drug sensitization is a major cause of relapse to drug use in addicts. In the present study the effects of intra-accumbal injections of L-arginine, the NO precursor and L-NAME, the NOS inhibitor on the morphine sensitization in Wistar rats (250-300 g) wer...

AIM To investigate effects of thenorphine, a new compound of partial agonist of mu-opioid receptor, on the locomotor activity and the behavioral sensitization to morphine in mice. METHODS Locomotor activity was observed after administration of thenorphine or co-administration of thenorphine and morphine in mice. Mice were induced behavioral sensitization to morphine by intraperitoneal injecti...

The aim of this study was to investigate role of the N-Methyl-D-Aspartate (NMDA) receptors in the decrease of morphine analgesia in mice after nociceptive sensitization. We used a hot plate test to assess effects of morphine on pain behavior in male NMRI mice. All drugs were administered through an intraperitoneal route. Sensitization schedule composed of 3-days pre-treatment of morphine (20mg/...

The nucleus accumbens (NAc) and the ventral tegmental area (VTA) are two major areas for the mesolimbic dopaminergic system which are strongly involved in the development of behavioral sensitization. In the present study, we investigated the role of D1/D2 dopaminergic receptors within the NAc or VTA in response to sensitization to morphine by the tail-flick test as a model of acute pain. Sensit...

De-novo protein synthesis is required in the development of behavioural sensitization. A prior screening test from our laboratory has implicated heat shock protein 70 (Hsp70) as one of the proteins required in this behavioural plasticity. Thus, this study was designed to extend our understanding of the role of Hsp70 in the development of behavioural sensitization induced by a single morphine ex...