Naphyrone, also known as NRG-1, is a novel psychoactive substance (NPS), a cathinone with stimulatory properties available on the grey/illicit drug market for almost a decade. It is structurally related to infamously known powerful stimulants with the pyrovalerone structure, such as alpha-pyrrolidinovalerophenone (α-PVP) or methylenedioxypyrovalerone (MDPV) that are labeled as a cheap replacement for cocaine and other stimulants. Despite the known addictive potential of α-PVP and MDPV, there are no studies directly evaluating naphyrone's addictive potential e.g., in conditioned place preference (CPP) test or using self-administration. Therefore, our study was designed to evaluate the addictive potential in a CPP test in male Wistar rats and compare its effect to another powerful stimulant with a high addictive potential - methamphetamine. Naphyrone increased time spent in the drug-paired compartment with 5 and 20 mg/kg s.c. being significant and 10 mg/kg s.c. reaching the threshold (p = 0.07); the effect was comparable to that of methamphetamine 1.5 mg/kg s.c. The lowest dose, naphyrone 1 mg/kg s.c., had no effect on CPP. Interestingly, no dose response effect was detected. Based on these data, we are able to conclude that naphyrone has an addictive potential and may possess a significant risk to users.

• MeSH
• alkaloidy farmakologie   MeSH
• chování zvířat účinky léků   MeSH
• klasické podmiňování účinky léků   MeSH
• krysa rodu rattus MeSH
• methamfetamin aplikace a dávkování   farmakologie   MeSH
• modely nemocí na zvířatech MeSH
• pentanony aplikace a dávkování   farmakologie   MeSH
• poruchy spojené s užíváním psychoaktivních látek * MeSH
• potkani Wistar MeSH
• pyrrolidiny aplikace a dávkování   farmakologie   MeSH
• stimulanty centrálního nervového systému aplikace a dávkování   farmakologie   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The hyperpolarization-activated cyclic-nucleotide-gated non-selective cation (HCN) channels play a potential role in the neurological basis underlying drug addiction. However, little is known about the role of HCN channels in methamphetamine (METH) abuse. In the present study, we examined the changes in working memory functions of METH re-exposed mice through Morris water maze test, and investigated the protein expression of HCN1 channels and potential mechanisms underlying the modulation of HCN channels by Western blotting analysis. Mice were injected with METH (1 mg/kg, i.p.) once per day for 6 consecutive days. After 5 days without METH, mice were re-exposed to METH at the same concentration. We found that METH re-exposure caused an enhancement of working memory, and a decrease in the HCN1 channels protein expression in both hippocampus and prefrontal cortex. The phosphorylated extracellular regulated protein kinase 1/2 (p-ERK1/2), an important regulator of HCN channels, was also obviously reduced in hippocampus and prefrontal cortex of mice with METH re-exposure. Meanwhile, acute METH exposure did not affect the working memory function and the protein expressions of HCN1 channels and p-ERK1/2. Overall, our data firstly showed the aberrant protein expression of HCN1 channels in METH re-exposed mice with enhanced working memory, which was probably related to the down-regulation of p-ERK1/2 protein expression.

• MeSH
• down regulace účinky léků   fyziologie   MeSH
• draslíkové kanály biosyntéza   MeSH
• hipokampus účinky léků   metabolismus   MeSH
• hyperpolarizační iontové kanály řízené cyklickými nukleotidy antagonisté a inhibitory   biosyntéza   MeSH
• krátkodobá paměť účinky léků   fyziologie   MeSH
• lokomoce účinky léků   fyziologie   MeSH
• methamfetamin aplikace a dávkování   toxicita   MeSH
• myši inbrední C57BL MeSH
• myši MeSH
• náhodné rozdělení MeSH
• prefrontální mozková kůra účinky léků   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Methamphetamine abuse imposes a significant burden on individuals and society worldwide, and an effective therapy of methamphetamine addiction would provide distinguished social benefits. Ghrelin significantly participates in reinforcing neurobiological mechanisms of stimulants, including amphetamines; thus, ghrelin antagonism is proposed as a promising addiction treatment. The aim of our study was to elucidate whether the pretreatment with growth hormone secretagogue receptor (GHS-R1A) antagonist, substance JMV2959, could reduce the methamphetamine intravenous self-administration (IVSA) and the tendency to relapse, and whether JMV2959 could reduce or prevent methamphetamine-induced conditioned place preference (CPP) in rats. Following an adequate maintenance period, JMV2959 3 mg/kg was administered intraperitoneally 20 min before three consequent daily 180 min sessions of methamphetamine IVSA under a fixed ratio FR1, which significantly reduced the number of active lever-pressings, the number of infusions, and the amount of the consumed methamphetamine dose. Pretreatment with JMV2959 also reduced or prevented relapse-like behavior tested in rats on the 12th day of the abstinence period. Pretreatment with JMV2959 significantly reduced the expression of methamphetamine-induced CPP. Simultaneous administration of JMV2959 with methamphetamine during the conditioning period significantly reduced the methamphetamine-CPP. Our results encourage further research of the ghrelin antagonism as a potential new pharmacological tool for methamphetamine addiction treatment.

• MeSH
• analýza rozptylu MeSH
• autoaplikace MeSH
• časové faktory MeSH
• glycin aplikace a dávkování   analogy a deriváty   farmakologie   MeSH
• intravenózní podání MeSH
• methamfetamin aplikace a dávkování   farmakologie   MeSH
• podmiňování (psychologie) účinky léků   MeSH
• potkani Wistar MeSH
• prostorové chování účinky léků   MeSH
• receptory ghrelinu antagonisté a inhibitory   metabolismus   MeSH
• stimulanty centrálního nervového systému aplikace a dávkování   farmakologie   MeSH
• tělesná hmotnost účinky léků   MeSH
• triazoly aplikace a dávkování   farmakologie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Chronic methamphetamine (meth) abuse often turns into a compulsive drug-taking disorder accompanied by persistent cognitive deficits and re-occurring psychosis. Possible common neurobiological substrates underlying meth-induced deficits and schizophrenia remain poorly understood. Serotonin 2A (5-HT2A) and metabotropic glutamate 2 (mGlu2) receptors co-regulate psychosis-like behaviors and cognitive function in animals. Therefore, in the present study we examined the effects of chronic exposure to three different drugs known to produce persistent deficits in sensorimotor gating and cognition [meth, phencyclidine (PCP) and MK-801] on the expression of 5-HT2A and mGlu2 within the rat medial prefrontal cortex (mPFC), dorsal hippocampus (dHPC) and perirhinal cortex (PRh). Adult male rats underwent 14 days of: (a) meth self-administration (6 h/day), (b) phencyclidine (PCP; 5 mg/kg, twice/day) administration, or (c) MK-801 (0.3 mg/kg, twice/day) administration. Seven days after the discontinuation of drug administration, tissues of interest were collected for protein expression analysis. We found that despite different pharmacological mechanism of action, chronic meth, PCP, and MK-801 similarly dysregulated 5-HT2A and mGlu2, as indicated by an increase in the 5-HT2A/mGlu2 expression ratio in the mPFC (all three tested drugs), PRh (meth and PCP), and dHPC (MK-801 only). Complementary changes in G-protein expression (increase in Gαq and decrease in Gαi) were also observed in the mPFC of meth animals. Finally, we found that 5-HT2A/mGlu2 cooperation can be mediated in part by the formation of the receptor heteromer in some, but not all cortical regions. In summary, these data suggest that a shift towards increased availability (and G-protein coupling) of cortical 5-HT2A vs. mGlu2 receptors may represent a common neurobiological mechanism underlying the emergence of psychosis and cognitive deficits observed in subjects with meth use disorder and schizophrenia.

• MeSH
• dizocilpinmaleát farmakologie   MeSH
• fencyklidin farmakologie   MeSH
• imunoprecipitace MeSH
• krysa rodu rattus MeSH
• methamfetamin aplikace a dávkování   farmakologie   MeSH
• perirhinální mozková kůra účinky léků   metabolismus   MeSH
• potkani Long-Evans MeSH
• potkani Wistar MeSH
• prefrontální mozková kůra účinky léků   metabolismus   MeSH
• protilátky imunologie   MeSH
• receptor serotoninový 5-HT2A imunologie   metabolismus   MeSH
• receptory metabotropního glutamátu metabolismus   MeSH
• reprodukovatelnost výsledků MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• srovnávací studie MeSH

Behavioral sensitization is defined as augmented psychomotor activity, which can be observed after drug re-administration following withdrawal of repeated drug exposure. It has been shown that abuse of one drug can lead to increased sensitivity to certain other drugs. This effect of developed general drug sensitivity is called cross-sensitization and has been reported between drugs with similar as well as different mechanisms of action. There is growing evidence that exposure to drugs in utero not only causes birth defects and delays in infant development, but also impairs the neural reward pathways, in the brains of developing offspring, in such a way that it can increase the tendency for drug addiction later in life. This review summarizes the results of preclinical studies that focused on testing behavioral cross-sensitization, after prenatal Methamphetamine exposure, to drugs administered in adulthood, with both similar and different mechanisms of action. Traditionally, behavioral sensitization has been examined using the Open field or the Laboras Test to record locomotor activity, and the Conditioned Place Preference and Self-administration test to examine drug-seeking behavior. However, it seems that prenatal drug exposure can sensitize animals not only to the locomotor-stimulating and conditioning effects of drugs, but may also be responsible for modified responses to various drug effects.

• MeSH
• lidé MeSH
• lokomoce účinky léků   fyziologie   MeSH
• methamfetamin aplikace a dávkování   škodlivé účinky   MeSH
• modely u zvířat * MeSH
• poruchy spojené s užíváním psychoaktivních látek etiologie   metabolismus   psychologie   MeSH
• stimulanty centrálního nervového systému aplikace a dávkování   MeSH
• těhotenství MeSH
• zpožděný efekt prenatální expozice chemicky indukované   metabolismus   psychologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

OBJECTIVES: Patients with schizophrenia often suffer comorbid substance abuse regardless of gender. However, the vast majority of studies are only conducted in male subjects. Therefore, the aim of these experiments is to assess addictive behaviors of both sexes in a neurodevelopmental model of schizophrenia induced by prenatal methylazoxymethanol (MAM) acetate exposure. METHODS: MAM (22 mg/kg) was administered intraperitoneally on gestational day 17. Two studies were performed in the offspring: (1) an alcohol-drinking procedure to assess daily intake of 20% alcohol and relapse-like behavior after a period of forced abstinence; (2) Methamphetamine (METH) intravenous self administration (IVSA) followed by forced abstinence and reinstatement phases. RESULTS: MAM exposure during the prenatal period did not change alcohol drinking regardless of sex. However, MAM females showed higher alcohol consumption in comparison to MAM males. The METH IVSA study revealed only a modest increase of drug consumption in MAM males, while there was no difference between the female groups. Reinstatement data showed no effect of the MAM model in either sex, but suggested increased responding in female rats. CONCLUSIONS: This study suggests that female sex and schizophrenia-like phenotype may work synergistically to enhance alcohol consumption. However, future research is needed to establish paradigms in which these findings would be readily assessed to test anti-addiction treatments.

• MeSH
• chování zvířat účinky léků   MeSH
• krysa rodu rattus MeSH
• methamfetamin aplikace a dávkování   MeSH
• methylazoxymethanolacetát analogy a deriváty   MeSH
• modely nemocí na zvířatech MeSH
• pití alkoholu patofyziologie   MeSH
• pohlavní dimorfismus MeSH
• potkani Sprague-Dawley MeSH
• schizofrenie chemicky indukované   komplikace   MeSH
• těhotenství MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Chronic methamphetamine (METH) abuse has been shown to elicit strong neurotoxic effects. Yet, with an increasing number of children born to METH abusing mothers maturing into adulthood, one important question is how far do the neurotoxic effects of METH alter various neurotransmitter systems in the adult METH-exposed offspring. The purpose of this study was to investigate long-term trans-generational neurochemical changes, following prenatal METH exposure, in the adult Wistar rat brain. METH or saline (SAL-control animals) was administered to pregnant dams throughout the entire gestation period (G0-G22). At postnatal day 90, dopamine, serotonin, glutamate and GABA were measured in the adult brain before (baseline) and after a METH re-administration using in vivo microdialysis and liquid chromatography/mass spectrometry. The results show that METH-exposure increased basal levels of monoamines and glutamate, but decreased GABA levels in all measured brain regions. Acute challenge with METH injection in the METH-exposed group induced a lower increase in the monoamine system relative to the increase in the GABAergic and glutamatergic system. The data show that prenatal METH exposure has strong effects on the monoaminergic, GABAergic and glutamatergic system even when exposure to METH was limited to the prenatal phase. Toxicological effects of METH have therefore longer lasting effects as currently considered and seem to affect the excitatory-inhibitory balance in the brain having strong implications for cognitive and behavioral functioning.

• MeSH
• dopamin metabolismus   MeSH
• GABA MeSH
• kyselina glutamová metabolismus   MeSH
• methamfetamin aplikace a dávkování   farmakokinetika   toxicita   MeSH
• mozek účinky léků   metabolismus   MeSH
• potkani Wistar MeSH
• serotonin metabolismus   MeSH
• těhotenství MeSH
• zpožděný efekt prenatální expozice * MeSH
• zvířata MeSH
• Check Tag
• těhotenství MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

• MeSH
• kognice účinky léků   MeSH
• lidé MeSH
• methamfetamin aplikace a dávkování   škodlivé účinky   MeSH
• poruchy spojené s užíváním amfetaminu patofyziologie   MeSH
• stimulanty centrálního nervového systému aplikace a dávkování   škodlivé účinky   MeSH
• translační biomedicínský výzkum organizace a řízení   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• úvodníky MeSH

Ketamine may prove to be a potential candidate in treating the widespread drug addiction/substance abuse epidemic among patients with schizophrenia. Clinical studies have shown ketamine to reduce cocaine and heroin cravings. However, the use of ketamine remains controversial as it may exacerbate the symptoms of schizophrenia. Therefore, the aim of this study is to characterize the effects of ketamine on drug addiction in schizophrenia using the methylazoxymethanol (MAM) acetate rat model on operant IV methamphetamine (METH) self-administration. MAM was administered intraperitoneally (22 mg/kg) on gestational day 17. Locomotor activity test and later IV self-administration (IVSA) were then performed in the male offspring followed by a period of forced abstinence and relapse of METH taking. After reaching stable intakes in the relapse phase, ketamine (5 mg/kg) was administered intraperitoneally 30 min prior to the self-administration session. As documented previously, the MAM rats showed a lack of habituation in the locomotor activity test but developed stable maintenance of METH self-administration with no difference in operant behaviour to control animals. Results show that ketamine treatment significantly reduced the METH intake in the control animals but not in MAM animals. Ketamine effect on METH self-administration may be explained by increased glutamatergic signalling in the prefrontal cortex caused by the N-methyl-D-aspartate antagonism and disinhibition of GABA interneurons which was shown to be impaired in the MAM rats. This mechanism may at least partly explain the clinically proven anti-craving potential of ketamine and allow development of more specific anti-craving medications with fewer risks.

• MeSH
• analýza rozptylu MeSH
• autoaplikace MeSH
• ketamin farmakologie   toxicita   MeSH
• krysa rodu rattus MeSH
• lokomoce účinky léků   MeSH
• methamfetamin aplikace a dávkování   MeSH
• methylazoxymethanolacetát analogy a deriváty   toxicita   MeSH
• modely nemocí na zvířatech MeSH
• operantní podmiňování účinky léků   MeSH
• potkani Sprague-Dawley MeSH
• schizofrenie chemicky indukované   farmakoterapie   MeSH
• stimulanty centrálního nervového systému aplikace a dávkování   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Drug addiction is commonly associated with depression and comorbid patients also suffer from higher cravings and increased relapse rate. To address this issue preclinically we combined the olfactory bulbectomy (OBX) model of depression and intravenous methamphetamine self-administration procedure in rats to assess differences in relapse-like behavior. Male Sprague-Dawley rats were divided randomly into two groups; in one group the bilateral olfactory bulbectomy (OBX) was performed while the other group was sham operated. After recovery, intracardiac catheter was implanted. Intravenous self-administration procedure was conducted in operant boxes using nose-poke operandi (Coulbourn Instruments, Inc., USA) under fixed ratio 1 schedule of reinforcement. Methamphetamine was available at dose 0.08 mg/kg/infusion. After stable methamphetamine intake was maintained, a period of forced abstinence was initiated and rats were kept in their home-cages for 14 days. Finally, one reinstatement session was conducted in operant boxes with no drug delivery. In the reinstatement session the mean of 138.4 active nose-pokes was performed by the OBX group, while the sham group displayed 41 responses, i.e. 140 % and 48 % of basal nose-poking during maintenance phase in OBX and sham operated group respectively. OBX group also showed significantly more passive nose-pokes indicating hyperactive behavioral traits in bulbectomized rats. However, the % of active operandum preference was equal in both groups. Olfactory bulbectomy model significantly increased reinstatement of methamphetamine seeking behavior. This paradigm can be used to evaluate potential drugs that are able to suppress the drug-seeking behavior.

• MeSH
• autoaplikace MeSH
• bulbus olfactorius patofyziologie   chirurgie   MeSH
• chování při shánění drogy fyziologie   MeSH
• depresivní poruchy komplikace   patofyziologie   MeSH
• intravenózní podání MeSH
• methamfetamin aplikace a dávkování   MeSH
• modely nemocí na zvířatech MeSH
• náhodné rozdělení MeSH
• operantní podmiňování účinky léků   fyziologie   MeSH
• poruchy spojené s užíváním amfetaminu komplikace   patofyziologie   MeSH
• potkani Sprague-Dawley MeSH
• recidiva MeSH
• stimulanty centrálního nervového systému aplikace a dávkování   MeSH
• zaváděcí katétry MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• validační studie MeSH