Introduction: N- nitro-L-arginine methyl ester (L-NAME), one of the L-arginine analogs, has been specified as an inhibitor of nitric oxide synthase ( NOS).Nitric oxide synthase is an enzyme which leads to nitric oxide synthesis. Since nitric oxide has been known as a pain mediator, it can be said that L-NAME can decrease and relieve pain. In this research the effect of L-NAME on morphine antino...

Morphine-induced signaling via opioid receptors (ORs) in dorsal root ganglia (DRG) neurons, the spinal cord, and various brain regions has been shown to modulate gene activity. Hitherto, little attention has been paid to extracellular signal-regulated kinases-1/2 (ERK-1/2)-mediated activation of the serum response factor (SRF) and ternary complex factors (TCFs) such as the E twenty six-like tra...

Introduction: The relation between morphine and nitric oxide release has been shown. Due to important role of nitric oxide in regulation of skin blood flow, the aim of this study was to investigate the effect of nitric oxide synthase inhibitor (L-NAME) and nitric oxide synthesis precursor (L-arginine) on skin blood flow of intact and morphine-dependent rats. Methods: Skin blood flow of hind pa...

As one of the most important diffused brain modulatory systems, the nucleus locus coeruleus (LC) receives most of its afferents from the nucleus paragigantocellularis (PGi) and plays a major role in the control of drug dependence and some emotional and exciting states. For detailed investigation of the effect of morphine on relationship between these two brain stem nuclei, the activity of the r...

BACKGROUND Role of nitric oxide (NO) in morphine-induced conditioned place preference (CPP) has already been proposed in the rat medial septum (MS), but no molecular evidence has been provided to clear this fact. METHODS Effects of intraseptal injections of L-arginine and/or NG-nitro-L-arginine methyl ester (L-NAME) on morphine place conditioning in Wistar rats were examined. Morphine (2.5-7....

OBJECTIVE(S) The aim of study was to investigate the antinociceptive effect of intracerebroventricular (ICV) microinjection of Origanum vulgare (ORG) extract and possible involvement of opioid receptors. MATERIALS AND METHODS Cannula was inserted into left ventricle of male rats. Five days after surgery Tail Flick Latency (TFL) was measured after ICV microinjection of, ORG (1, 3 and 6 µg / ra...

introduction: morphine addiction and morphine withdrawal syndrome are the two main problems of today’s human society. the present study has investigated the effects of nicotine on the strength of physical and psychological dependency in single and repeated doses morphine administrated rats. methods: male wistar rats were subjected to morphine consumption with single or frequent dose protocols. ...