Involvement of adenosine receptor agonists on the development of hypersensitivity to acute dose of morphine during morphine withdrawal period.
Journal Title: Pharmacological Reports - Year 2008, Vol 60, Issue 5
Abstract
In the present study, the involvement of the selective adenosine A(1) (CPA) and A(2A) (CGS 21680) and non-selective adenosine A(1)/A(2A) (NECA) receptor agonists on the development of hypersensitivity to acute morphine injection given during opiate withdrawal was investigated. Intraperitioneal (ip) injections of morphine at increasing doses (10, 20, 30, 40, 50 mg/kg) for 6 consecutive days produced a state of dependence. On the 6th day, in the morning, animals were injected with the last dose of morphine (50 mg/kg, ip). Each day, 20 min before each injection of morphine, adenosine receptor agonists were also administered. Seven days after cessation of the morphine treatment, on the 13th day of the experiment, all animals were challenged with a dose of morphine (10 mg/kg, ip). A clear increase in locomotor activity was observed, indicating that hypersensitivity had developed. Our study has demonstrated the presence of an attenuating effect of adenosinergic drugs, such as CGS 21680 and NECA, but not CPA, on the development of hypersensitivity. The results indicate that stimulation of the adenosine A(2A) receptor plays some role in modulating the neuroadaptive changes appearing during chronic opioid treatment and that adenosine A(2A) receptor agonists may serve as useful drugs in relapse protection. Our investigations focused on adenosine A(2A) agonists as possible vehicles for pharmacotherapy for morphine addiction.
Authors and Affiliations
Joanna Listos, Sylwia Talarek
Effect of risperidone on the fluoxetine-induced changes in extracellular dopamine, serotonin and noradrenaline in the rat frontal cortex.
Background: Several clinical reports have documented a beneficial effect of the addition of a low dose of risperidone to the ongoing treatment with antidepressants, in particular selective serotonin reuptake inhibitors,...
Effect of human interleukin-10 on the expression of nitric oxide synthases in the MPTP-based model of Parkinson's disease.
Background: Parkinson's disease (PD) is the second most common progressive neurodegenerative disorder. The degeneration of the nigro-striatal pathway has been linked with the inflammatory process accompanied by the robus...
Serotonin 2A receptor gene (HTR2A) polymorphism in alcohol-dependent patients.
Background: The serotonergic (5-HT) dysfunction has been frequently described in subjects with alcohol dependence (AD). In the present study, a potential relationship between T102C polymorphism in the 5-HT receptor subty...
Caffeine metabolism during prolonged treatment of rats with antidepressant drugs.
Our previous studies showed that some of the tested antidepressants (tricyclics, SSRIs, mirtazapine, nefazodone) directly inhibited the metabolism of caffeine when added in vitro to liver microsomes. The aim of the prese...
α1-Adrenergic receptor subtypes in the central nervous system: insights from genetically engineered mouse models.
α1-Adrenergic receptors (α1-ARs) are important players in peripheral and central nervous system (CNS) regulation and function and in mediating various behavioral responses. The α1-AR family consists of three subtypes, α1...