The mesocorticolimbic dopaminergic system plays an important role in the reinforcing effects of drugs of abuse, and the activity-dependent synaptic plasticity of the system is involved in drug dependence. A DNA microarray screening revealed that the expression levels of tissue plasminogen activator (tPA) mRNA in the nucleus accumbens of morphine- or methamphetamine-dependent rats were significa...

To investigate an involvement of catecholamines and/or the cyclic adenosine monophosphate (cAMP) systems in the development of drug dependence, we examined whether phencyclidine (PCP) and morphine dependence were developed in tyrosine hydroxylase (TH) heterozygous (TH) and cAMP response element binding protein (CREB) binding protein (CBP) heterozygous (CBP) mice. PCP (8 mg/kg) induced place pre...

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 gro...

in this study the effect of adenosine and caffeine on spontaneous activity of paragigantocellularis (pgi) neurons was investigated. the spontaneous activity of pgi neurons was significantly decreased by microinjection of adenosine (10 nm, 0.5 µl) into pgi nucleus of both control and morphine-dependent rats. the decrease in firing rate of pgi neurons of morphine-dependent rats was greater than t...

The striatum is believed to be a crucial brain region associated with drug reward. Adaptive alteration of neurochemistry in this area might be one potential mechanism underlying drug dependence. It has been proposed that the dysfunction of Na+,K+-ATPase function is involved in morphine tolerance and dependence. The present study, therefore, was undertaken to study the adaptation of the striatal...

Objective(s): Morphine dependence (MD) potently protects heart against ischemia reperfusion (IR) injury through specific signaling mechanisms, which are different from the pathways involved in acute morphine treatment or classical preconditioning. Since opioid receptor density changes post cerebral ischemia strongly correlated with brain histological damage, in the present study, we tried to el...

The role of glutamate receptors within the nucleus accumbens in morphine tolerance has been postulated. Previous studies have reported that glutamate receptors exert their effects in part through the release of nitric oxide (NO). In the present study, the effect of intra-accumbal injections of L-arginine, the NO precursor and L-NAME, the NOS inhibitor on the morphine tolerance in Wistar rats (2...

introduction: abusing drugs such as morphine continues to be a serious medical and social problem. defining a habit that increases the devastating effect such as compulsive use and craving is necessary. methods: this experiment was designed in four groups 1) group-housed (gh) 2) isolation 3) group-housed morphine-treated (ghmt) (4) isolated-housed morphine-treated (ihmt). rats were received mor...