In the present study, interactive effects of D1 and D2 dopamine receptors antagonists and different periods of lithium pretreatment on morphine dependence in mice have been investigated. This study was designed to investigate whether the hypothesis that lithium and dopaminergic mechanisms via their effects on phosphoinositide pathways and calcium flux could influence morphine withdrawal respons...

In drug-free subjects, a single dose of morphine followed by an opioid antagonist a few hours later results in signs of a withdrawal syndrome, suggesting a state of physical dependence. Increased urination/defecation, altered startle, and ultrasonic vocalizations (USV) are some signs of the withdrawal syndrome in rats chronically dependent on morphine. We investigated whether naltrexone stimula...

Opioid receptor agonists are effective for treating pain; however, tolerance and dependence can develop with repeated use. Combining opioids with cannabinoids can enhance their analgesic potency, although it is less clear whether combined treatment alters opioid tolerance and dependence. In this study, four monkeys received 3.2 mg/kg morphine alone or in combination with 1 mg/kg Δ(9)-tetrahydro...

Introduction: Some studies indicate changes in the level of thyroid hormones in addicted people. Also, there are some reports concerning the modulation of hypothalamus-hypophysis-thyroid axis in the context of morphine addiction. In the present study, the effects of thyroid gland activation via the acute and chronic administration of levothyroxine on morphine withdrawal syndrome were investi...

Repeated low-dose morphine treatment facilitates delayed-escape behaviour of hippocampus-dependent Morris water maze and morphine withdrawal influences hippocampal NMDA receptor-dependent synaptic plasticity. Here, we examined whether and how morphine withdrawal influenced delayed-escape behaviour and NR2A/2B expression ratio of hippocampal synaptosomes. We found that both delayed-escape behavi...

the effect of aqueous extract of nepata glomerulosa boiss. aerial parts on morphine withdrawal syndrome was investigated in mice. dependence was induced by subcutaneous injections of morphine for 3 consecutive days. on day 4, morphine was injected 2 h prior to intraperitoneal injection of naloxone. the number of jumps during a 20 min. period after naloxone injection was considered as a measure ...

combined use of an opioid with a psychostimulant is popular among drug abusers. such “polydrug use” may increase drug effects or attenuate adverse effects of either drug alone. we proposed that a combination of methamphetamine (meth) and morphine may change physical opioid withdrawal symptoms. adult male rats were chronically injected with cumulative subcutaneous (s.c.) doses of morphine, meth ...

The Lewis (LEW) and Fischer 344 (F344) inbred rat strains react differentially to acute morphine administration for a variety of behavioral and neurochemical measures. Investigations into effects of chronic morphine are less common, and investigations assessing dependence have been limited to those utilizing antagonist-precipitated withdrawal. The present experiment extended these assessments b...

Several lines of evidence suggest a crucial involvement of glutamate in the mechanism of drug addiction. The involvement of group I mGlu receptors in the mechanism of addiction has also been proposed. Given the recent discovery of selective and brain penetrable mGlu5 receptor antagonists, the effects of 3-[(2-methyl-1,3-thiazol-4-yl)ethynyl]-pyridine (MTEP) were evaluated in the naloxone-precip...