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1.
Behav Neurosci ; 138(2): 85-93, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38661668

RESUMO

Rodent behavioral studies have largely focused on male animals, which has limited the generalizability and conclusions of neuroscience research. Working with humans and rodents, we studied sex effects during interval timing that requires participants to estimate an interval of several seconds by making motor responses. Interval timing requires attention to the passage of time and working memory for temporal rules. We found no differences between human females and males in interval timing response times (timing accuracy) or the coefficient of variance of response times (timing precision). Consistent with prior work, we also found no differences between female and male rodents in timing accuracy or precision. In female rodents, there was no difference in interval timing between estrus and diestrus cycle stages. Because dopamine powerfully affects interval timing, we also examined sex differences with drugs targeting dopaminergic receptors. In both female and male rodents, interval timing was delayed after administration of sulpiride (D2-receptor antagonist), quinpirole (D2-receptor agonist), and SCH-23390 (D1-receptor antagonist). By contrast, after administration of SKF-81297 (D1-receptor agonist), interval timing shifted earlier only in male rodents. These data illuminate sex similarities and differences in interval timing. Our results have relevance for rodent models of both cognitive function and brain disease by increasing representation in behavioral neuroscience. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Percepção do Tempo , Feminino , Masculino , Animais , Percepção do Tempo/fisiologia , Percepção do Tempo/efeitos dos fármacos , Humanos , Caracteres Sexuais , Dopamina/metabolismo , Ratos , Receptores de Dopamina D2/metabolismo , Sulpirida/farmacologia , Quimpirol/farmacologia , Agonistas de Dopamina/farmacologia , Agonistas de Dopamina/administração & dosagem , Antagonistas de Dopamina/farmacologia , Antagonistas de Dopamina/administração & dosagem , Adulto , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia , Benzazepinas/farmacologia , Adulto Jovem , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D1/antagonistas & inibidores , Memória de Curto Prazo/fisiologia , Memória de Curto Prazo/efeitos dos fármacos
2.
Eur J Neurosci ; 59(7): 1558-1566, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38308520

RESUMO

The excitation-inhibition imbalance manifesting as epileptic activities in Alzheimer's disease is gaining more and more attention, and several potentially involved cellular and molecular pathways are currently under investigation. Based on in vitro studies, dopamine D1-type receptors in the anterior cingulate cortex and the hippocampus have been proposed to participate in this peculiar co-morbidity in mouse models of amyloidosis. Here, we tested the implication of dopaminergic transmission in vivo in the Tg2576 mouse model of Alzheimer's disease by monitoring epileptic activities via intracranial EEG before and after treatment with dopamine antagonists. Our results show that neither the D1-like dopamine receptor antagonist SCH23390 nor the D2-like dopamine receptor antagonist haloperidol reduces the frequency of epileptic activities. While requiring further investigation, our results indicate that on a systemic level, dopamine receptors are not significantly contributing to epilepsy observed in vivo in this mouse model of Alzheimer's disease.


Assuntos
Doença de Alzheimer , Amiloidose , Epilepsia , Camundongos , Animais , Antagonistas de Dopamina/farmacologia , Doença de Alzheimer/tratamento farmacológico , Receptores de Dopamina D2/metabolismo , Benzazepinas/farmacologia , Benzazepinas/uso terapêutico , Receptores de Dopamina D1/metabolismo , Epilepsia/tratamento farmacológico , Modelos Animais de Doenças , Amiloidose/tratamento farmacológico
3.
Behav Brain Res ; 463: 114914, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38368953

RESUMO

Previous studies have shown that various receptors, including dopamine receptors, are expressed in the hippocampal dentate gyrus (DG). Besides, indicatively, dopamine receptors play an essential role in the modulation of pain perception. On the other hand, stressful experiences can produce analgesia, termed stress-induced analgesia (SIA). The current study examined the probable role of dopamine receptors within the DG in antinociception induced by restraint stress (RS). Ninety-seven male albino Wistar rats were unilaterally implanted with a cannula in the DG. Animals received intra-DG microinjections of SCH23390 or Sulpiride (0.25, 1, and 4 µg/rat) as D1-and D2-like dopamine receptor antagonists, respectively, five minutes before RS. Ten minutes after the end of the induction of RS for three hours, 50 µl 2.5% formalin was injected subcutaneously into the plantar surface of the hind paw to induce persistent inflammatory pain. Pain scores were evaluated at 5-minute intervals for 60 minutes. These findings showed that; exposure to RS for three hours produced SIA in both phases of the formalin test, while this RS-induced analgesia was attenuated in the early and late phases of the formalin test by intra-DG microinjection of SCH23390 and Sulpiride. The results of the present study suggested that both D1- and D2-like dopamine receptors in the DG have a considerable role in the induced analgesia by RS.


Assuntos
Receptores Dopaminérgicos , Sulpirida , Ratos , Masculino , Animais , Sulpirida/farmacologia , Medição da Dor , Receptores Dopaminérgicos/fisiologia , Analgésicos/efeitos adversos , Dor/induzido quimicamente , Ratos Wistar , Giro Denteado/metabolismo , Hipocampo/metabolismo , Receptores de Dopamina D1/metabolismo , Benzazepinas/farmacologia
4.
Drug Alcohol Depend ; 255: 111063, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38163425

RESUMO

BACKGROUND: Cocaine use disorder (CUD) is a major public health problem for which there is no approved pharmacotherapy. The primary purpose of this study was to evaluate the ability of lorcaserin, a 5-hydroxytryptamine2 C (5-HT2 C) receptor agonist, to facilitate abstinence in individuals seeking treatment for CUD. METHODS: This was a 12-site, randomized, parallel arm study with a 13-week Treatment Phase that included a 1-week, single-blind run-in period when all participants received twice daily 15mg acetazolamide capsules (a medication adherence marker), followed by randomization to either twice daily 10mg lorcaserin or placebo capsules for the remaining 12 weeks. Pre-randomization data were utilized in an enrichment strategy aimed at achieving high levels of medication adherence and low placebo response rates in a subgroup of participants that qualified for the "efficacy population." For lorcaserin vs. placebo, the primary efficacy endpoint was the proportion of participants in the efficacy population achieving abstinence during the last three weeks of treatment, as evidenced by self-report of no cocaine use, confirmed by urine testing. RESULTS: Within the efficacy population, 1.1% of 91 participants receiving lorcaserin and 4.3% of 92 receiving placebo achieved abstinence during the last 3 weeks of treatment. Among all randomized participants, 2.5% of 118 receiving lorcaserin and 5.6% of 124 receiving placebo achieved similar abstinence. Study participants receiving lorcaserin exhibited significantly greater reductions in body weight and BMI, indicating that medication adherence was sufficient to produce a pharmacological effect. CONCLUSIONS: Twice daily 10mg lorcaserin failed to demonstrate efficacy in the treatment of CUD.


Assuntos
Benzazepinas , Cocaína , Humanos , Método Simples-Cego , Peso Corporal , Benzazepinas/farmacologia , Método Duplo-Cego , Resultado do Tratamento
5.
Acta Physiol (Oxf) ; 240(3): e14085, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38230890

RESUMO

Myocardial infarction (MI) and its associated complications including ventricular arrhythmias and heart failure are responsible for a significant incidence of morbidity and mortality worldwide. The ensuing cardiomyocyte loss results in neurohormone-driven cardiac remodeling, which leads to chronic heart failure in MI survivors. Ivabradine is a heart rate modulation agent currently used in treatment of chronic heart failure with reduced ejection fraction. The canonical target of ivabradine is the hyperpolarization-activated cyclic nucleotide-gated channels (HCN) in cardiac pacemaker cells. However, in post-MI hearts, HCN can also be expressed ectopically in non-pacemaker cardiomyocytes. There is an accumulation of intriguing evidence to suggest that ivabradine also possesses cardioprotective effects that are independent of heart rate reduction. This review aims to summarize and discuss the reported cardioprotective mechanisms of ivabradine beyond heart rate modulation in myocardial infarction through various molecular mechanisms including the prevention of reactive oxygen species-induced mitochondrial damage, improvement of autophagy system, modulation of intracellular calcium cycling, modification of ventricular electrophysiology, and regulation of matrix metalloproteinases.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Humanos , Ivabradina/farmacologia , Ivabradina/uso terapêutico , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização , Frequência Cardíaca/fisiologia , Benzazepinas/farmacologia , Infarto do Miocárdio/tratamento farmacológico , Insuficiência Cardíaca/tratamento farmacológico , Miócitos Cardíacos
6.
CNS Neurol Disord Drug Targets ; 23(3): 278-283, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37005521

RESUMO

Lorcaserin is a 3-benzazepine that binds 5-HT2C serotonin receptors in the hypothalamus, where it mediates lack of hunger and/or satiety, and in the ventral tegmental area, the site of origin of the mesolimbic and mesocortical dopaminergic projections, which mediate pleasure and reward. The drug has been first developed for the treatment of obesity, where it has shown efficacy, and subsequently trialed to counter substance use (mostly cocaine, cannabis, opioids, and nicotine) and craving, but showed inconsistent effects. Since 2020, the US Food and Drug Administration obtained that the drug was voluntarily withdrawn from the US market on the grounds that its long-term use was found to be associated with a greater incidence of some types of cancer. Provided it can show to be free from cancerogenic effects, ongoing research suggests that lorcaserin may have therapeutic potential for a variety of disorders and conditions beyond obesity. Since 5-HT2C receptors are involved in many diversified physiological functions (mood, feeding, reproductive behavior, neuronal processes related to impulsiveness, and modulating reward-related mechanisms) this drug has the potential to treat different central nervous system conditions, such as depression and schizophrenia.


Assuntos
Agonistas do Receptor 5-HT2 de Serotonina , Serotonina , Humanos , Agonistas do Receptor 5-HT2 de Serotonina/uso terapêutico , Benzazepinas/farmacologia , Benzazepinas/uso terapêutico , Obesidade/tratamento farmacológico
7.
Pharmacol Biochem Behav ; 234: 173673, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37951365

RESUMO

Lorcaserin, a selective serotonin 2C (5-HT2C) receptor agonist, was approved for treating obesity and has been investigated for treating substance use disorders including those involving opioids. Although lorcaserin was withdrawn from the market, interest in the therapeutic potential of drugs acting at 5-HT2C receptors continues, supporting the need to further characterize potential adverse effects especially when combined with drugs of abuse. This study examined acute effects of lorcaserin on opioid-induced ventilatory depression, which is the primary cause of overdose, and opioid self-administration, which models factors contributing to opioid abuse, in male and female rhesus monkeys. In one group (n = 4), effects of morphine (0.178 to 5.6 mg/kg, s.c.), fentanyl (0.0032 to 0.1 mg/kg, s.c.), and lorcaserin (0.1 to 1.78 mg/kg, s.c.) alone as well as effects of lorcaserin with each opioid on ventilation were determined using head plethysmography. Another group (n = 5) responded under a food versus fentanyl (0.1 to 3.2 µg/kg/infusion, i.v.) choice procedure, and lorcaserin (0.32 to 1.78 mg/kg, i.v.) was given as a pretreatment. Lorcaserin dose-dependently decreased minute volume to below 70 % of baseline when administered alone and increased the potency of morphine and fentanyl. Consistent with previous studies, lorcaserin failed to alter choice of fentanyl over food. This study demonstrates the novel finding that lorcaserin alone decreases ventilation and enhances the ventilatory-depressant effects of opioids. Taken together with previous studies, these results suggest that combining a 5-HT2C receptor agonist such as lorcaserin with an opioid could increase the risk of ventilatory depression without the benefit of decreasing abuse.


Assuntos
Analgésicos Opioides , Insuficiência Respiratória , Masculino , Feminino , Humanos , Analgésicos Opioides/efeitos adversos , Preparações Farmacêuticas , Serotonina , Benzazepinas/farmacologia , Benzazepinas/uso terapêutico , Morfina , Fentanila/efeitos adversos , Relação Dose-Resposta a Droga
9.
Pharmacol Biochem Behav ; 234: 173678, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37979731

RESUMO

Multiple interacting neural systems are involved in sustaining nicotine reinforcement. We and others have shown that dopamine D1 receptors and glutamate NMDA receptors both play important roles in nicotine reinforcement. Blockade of D1 receptors with the antagonist SCH-23390 (0.02 mg/kg) both acutely and chronically significantly decreased nicotine self-administration in rats. Blockade of NMDA receptors (10 mg/kg) acutely with memantine significantly increased nicotine self-administration, but chronic blockade of NMDA receptors with memantine significantly decreased nicotine self-administration. The current study examined the interactions of acute and chronic administration of SCH-23390 and memantine on nicotine self-administration in female rats. Replicating earlier studies, acute and chronic SCH-23390 significantly decreased nicotine self-administration and memantine had a biphasic effect with acute administration increasing nicotine self-administration and chronic memantine showed a non-significant trend toward decreasing it. However, chronic interaction study showed that memantine significantly attenuated the decrease in nicotine self-administration caused by chronic SCH-23390. These studies provide important information that memantine attenuates the efficacy of D1 antagonist SCH 23390 in reducing nicotine-self-administration. These two drugs do not appear to have mutually potentiating effects to aid tobacco cessation.


Assuntos
Antagonistas de Dopamina , Nicotina , Ratos , Feminino , Animais , Nicotina/farmacologia , Antagonistas de Dopamina/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Dopamina , N-Metilaspartato , Memantina/farmacologia , Receptores de N-Metil-D-Aspartato , Ratos Sprague-Dawley , Receptores de Dopamina D1/metabolismo , Benzazepinas/farmacologia
10.
Pharmacol Biochem Behav ; 235: 173702, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38154590

RESUMO

Smoking is the leading cause of preventable death worldwide, with <7 % of smoking cessation attempts being met with success. Nicotine, the main addictive agent in cigarettes, enhances the reinforcing value of other environmental rewards. Under some circumstances, this reward enhancement maintains nicotine consumption. Varenicline (i.e., cessation aid Chantix™) also has reward-enhancement effects via nicotinic acetylcholine receptor agonism (nAChRs) - albeit less robust than nicotine. Cotinine is the major metabolite of nicotine. Recent studies suggest that cotinine is a positive allosteric modulator (PAM) and/or a weak agonist at nAChRs. Thus, cotinine may enhance the behavioral effects of nAChR compounds such as varenicline and/or exert some behavioral effects alone. We used 20 (10M, 10F) Sprague-Dawley rats to assess reward-enhancement within-subjects by examining responding maintained by a reinforcing visual stimulus on a Variable Ratio 2 schedule of reinforcement. To assess the reward-enhancing effects of cotinine, rats received one injection of cotinine (saline, 0.1, 0.3, 1.0, 3.0, 6.0 mg/kg) before each 1 h session. To assess cotinine and varenicline interactions, rats received an injection of cotinine (saline, 0.1, 1.0, or 6.0 mg/kg) and of varenicline (saline, 0.1, 0.3, 1.0, or 3.0 mg/kg) before the session. While we replicated prior work identifying reward-enhancement by 0.1, 0.3, and 1.0 mg/kg varenicline, cotinine alone did not produce reward-enhancement nor augment the reward-enhancing effects of varenicline. Future studies may consider examining the reward-enhancing effects of cotinine with other reinforcers or co-administered with other smoking cessation aids such as bupropion.


Assuntos
Nicotina , Receptores Nicotínicos , Humanos , Ratos , Animais , Vareniclina/farmacologia , Nicotina/farmacologia , Cotinina/farmacologia , Ratos Sprague-Dawley , Agonistas Nicotínicos/farmacologia , Receptores Nicotínicos/metabolismo , Benzazepinas/farmacologia , Quinoxalinas/farmacologia
11.
Behav Brain Res ; 453: 114638, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37619769

RESUMO

Mitragynine (MG) is the primary active constituent of Mitragyna speciosa Korth (kratom), a psychoactive Southeast Asian plant with potential therapeutic use. Numerous studies support roles of dopaminergic system in drug reward. However, the involvement of the dopaminergic system in mediating MG reward and drug-seeking is poorly understood. Using conditioned place preference (CPP) paradigm, the present study aims to evaluate the roles of the dopamine (DA) D1 receptor in the acquisition and expression of MG-induced CPP in rats. The effects of SCH-23390, a selective DA D1 receptor antagonist, on the acquisition of MG-induced CPP were first investigated. Rats were pre-treated systemically with SCH-23390 (0, 0.1 and 0.3 mg/kg, i.p.) prior to MG (10 mg/kg) conditioning sessions. Next, we tested the effects of the DA D1 receptor antagonist on the expression of MG-induced CPP. Furthermore, the effects of a MG-priming dose (5 mg/kg) on the reinstatement of extinguished CPP were tested. The results showed that SCH-23390 dose-dependently suppressed the acquisition of a MG-induced CPP. In contrast, SCH-23390 had no effect on the expression of a MG-induced CPP. The findings of this study suggested a crucial role of the DA D1 receptor in the acquisition, but not the expression of the rewarding effects of MG in a CPP test. Furthermore, blockade of the D1-like receptor during conditioning did not prevent MG priming effects on CPP reinstatement test, suggesting no role for the DA D1 receptor in reinstatement sensitivity.


Assuntos
Receptores de Dopamina D1 , Animais , Ratos , Benzazepinas/farmacologia , Dopamina , Antagonistas de Dopamina/farmacologia
12.
Mol Neurobiol ; 60(12): 7238-7252, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37542648

RESUMO

N-Methyl-D-aspartate receptors (NMDARs) composed of different splice variants display distinct pH sensitivities and are crucial for learning and memory, as well as for inflammatory or injury processes. Dysregulation of the NMDAR has been linked to diseases like Parkinson's, Alzheimer's, schizophrenia, and drug addiction. The development of selective receptor modulators, therefore, constitutes a promising approach for numerous therapeutical applications. Here, we identified (R)-OF-NB1 as a promising splice variant selective NMDAR antagonist. We investigated the interaction of (R)-OF-NB1 and NMDAR from a biochemical, bioinformatical, and electrophysiological perspective to characterize the downstream allosteric modulation of NMDAR by 3-benzazepine derivatives. The allosteric modulatory pathway starts at the ifenprodil binding pocket in the amino terminal domain and immobilizes the connecting α5-helix to the ligand binding domain, resulting in inhibition. In contrast, the exon 5 splice variant GluN1-1b elevates the NMDARs flexibility and promotes the open state of its ligand binding domain.


Assuntos
Benzazepinas , Receptores de N-Metil-D-Aspartato , Ligantes , Benzazepinas/farmacologia , Éxons , Aprendizagem
13.
Molecules ; 28(16)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37630262

RESUMO

The 1-phenylbenzazepine template has yielded a number of D1R-like ligands, which, though useful as pharmacological tools, have significant drawbacks in terms of selectivity versus D5R as well as pharmacokinetic behavior. A number of 1-phenylbenzazepines contain a 6-chloro functional group, but extensive SAR studies around the 6-chloro-1-phenylbenzazepine framework have not been reported in the literature. To further understand the tolerance of the 6-chloro-1-phenylbenzazepine template for various substituent groups towards affinity and selectivity at D1R, we synthesized two series of analogs with structural variations at the C-7, C-8, N-3, C-3' and C-4' positions. The series 2 analogs differed from series 1 analogs in possessing a nitrogenated functionality at C-8 and lacked a C-4' substituent, but were otherwise similar. Analogs were assessed for affinity at D1R, D2R and D5R. For both series, we found that the analogs lacked affinity for D2R and showed modest D1R versus D5R selectivity. For series 1 analogs, an N-3 methyl substituent group was better tolerated than N-H or an N-3 allyl substituent. The C-8 position appears to be tolerant of amino and methanesulfonamide substituents for high D1R affinity, but C-8 amides displayed low to moderate D1R affinities. A C-3' methyl substituent appeared to be critical for the D1R affinity of some analogs, but the C-4' substituents tried (hydroxy and methoxy; series 1) did not result in any significant boost in D1R affinity. Compound 15a was the most potent and selective D1R ligand identified from these studies (Ki at D1R = 30 nM; 6-fold selectivity versus D5R). Further functional activity assessments indicate that 15a functions as a D1R antagonist towards cAMP-mediated signaling. The predicted drug-like properties of 15a are encouraging for further pharmacological assessments on the compound.


Assuntos
Amidas , Receptores de Dopamina D1 , Benzazepinas/farmacologia , Antagonistas de Dopamina , Relação Estrutura-Atividade
14.
Int J Mol Sci ; 24(15)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37569468

RESUMO

Tobacco smoking is one of the most serious health problems. Potentially lethal effects of nicotine for adults can occur with as little as 30 to 60 mg, although severe symptoms can arise with lower doses. Furthermore, the route of administration also influences the toxicity. Cytisine is one of the most popular medications in nicotinism treatment. Like nicotine, cytisine is a plant alkaloid, signaling through nicotinic acetylcholine receptors. Our study evaluated the effects of cytisine in nicotine-induced embryotoxic effects using zebrafish larvae. We examined the teratogenicity of nicotine and cytisine alone or in combination. Nicotine increased mortality and delayed hatching of zebrafish larvae in a dose-dependent manner. Cytisine did not affect mortality in a wide range of concentrations, and hatching delay was observed only at the highest concentrations, above 2 mM. Administering compounds together partially reduced the adverse teratogenic effect induced by nicotine alone. The protective effect of cytisine against the nicotine effect, observed in zebrafish, will contribute to future studies or treatments related to nicotine addiction or prenatal nicotine exposure in humans.


Assuntos
Alcaloides , Receptores Nicotínicos , Humanos , Animais , Nicotina/efeitos adversos , Peixe-Zebra , Agonistas Nicotínicos/farmacologia , Vareniclina , Benzazepinas/farmacologia , Quinoxalinas/farmacologia , Alcaloides/farmacologia , Alcaloides/uso terapêutico , Azocinas/toxicidade , Quinolizinas/farmacologia
15.
Behav Brain Res ; 452: 114562, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37394124

RESUMO

The mutant bate-palmas ("claps"; symbol - bapa) mice induced by the mutagenic chemical ENU present motor incoordination and postural alterations. A previous study showed that bapa mice present increased motor/exploratory behaviors during the prepubertal period due to increased striatal tyrosine hydroxylase expression, suggesting striatal dopaminergic system hyperactivity. This study aimed to evaluate the involvement of striatal dopaminergic receptors in the hyperactivity of bapa mice. Male bapa mice and their wild strain (WT) were used. Spontaneous motor behavior was observed in the open-field test, and stereotypy was evaluated after apomorphine administration. The effects of DR1 and DR2 dopaminergic antagonists (SCH-23,390; sulpiride) and the striatal DR1 and D2 receptor gene expression were evaluated. Relative to WT, bapa mice showed: 1) increased general activity for four days; 2) increased rearing and sniffing behavior and decreased immobility after apomorphine; 3) blockage of rearing behavior after the DR2 antagonist but no effect after DR1 antagonist; 4) blockage of sniffing behavior after the DR1 antagonist in bapa and WT mice but no effect after the DR2 antagonist; 5) increased immobility after the DR1 antagonist but no effect after the DR2 antagonist; 6) increased expression of striatal DR1 receptor gene and reduced the DR2 expression gene after apomorphine administration. Bapa mice showed increased activity in open field behavior. The increased rearing behavior induced by apomorphine of bapa mice resulted from the increased gene expression of the DR1 receptor.


Assuntos
Apomorfina , Benzazepinas , Animais , Masculino , Camundongos , Apomorfina/farmacologia , Benzazepinas/farmacologia , Dopamina , Antagonistas de Dopamina/farmacologia , Receptores de Dopamina D1 , Sulpirida/farmacologia
16.
Addict Biol ; 28(8): e13312, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37500487

RESUMO

The use of nicotine and tobacco products is highly addictive. The dopaminergic system plays a key role in the initiation and maintenance of nicotine intake. Dopamine D1-like receptor blockade diminishes nicotine intake in rats with daily short (1 h) access to nicotine, but little is known about the effects of dopamine receptor antagonists or agonists on nicotine intake in rats with intermittent long (23 h) access. Because of the extended access conditions and high nicotine intake, the intermittent long access procedure might model smoking and vaping better than short access models. We investigated the effects of the dopamine D1-like receptor antagonist SCH 23390 and the D1-like receptor agonist A77636 on nicotine intake in male rats with intermittent short or long access to nicotine. The rats self-administered nicotine for 5 days (1 h/day) and were then given 15 intermittent short (1 h/day) or long (23 h/day) access sessions (3 sessions/week, 0.06 mg/kg/inf). The D1-like receptor antagonist SCH 23390 decreased nicotine intake to a similar degree in rats with short or long access to nicotine. The D1-like receptor agonist A77636 induced a greater decrease in nicotine intake in the rats with long access to nicotine than in rats with short access. Treatment with A77636 induced a prolonged decrease in nicotine intake that lasted throughout the dark and light phase in the long access rats. These findings indicate that blockade and stimulation of D1-like receptors decrease nicotine intake in an intermittent long access animal model that closely models human smoking and vaping.


Assuntos
Dopamina , Nicotina , Humanos , Ratos , Masculino , Animais , Nicotina/farmacologia , Receptores de Dopamina D1 , Benzopiranos , Benzazepinas/farmacologia
17.
Psychopharmacology (Berl) ; 240(8): 1651-1666, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37378887

RESUMO

RATIONALE: Dopaminergic dysfunction is implicated in disorders of impulsivity and inattention. The rodent continuous performance test (rCPT) has been used to quantify changes in attention and impulsivity. OBJECTIVE: To examine the roles of dopamine receptors in attention and impulsivity behaviours measured in the rCPT variable stimulus duration (vSD) and the variable intertrial interval schedules (vITI) using DA receptor antagonists. METHODS: Two cohorts of 35 and 36 female C57BL/6JRj mice were examined separately in the rCPT, vSD, and vITI schedules, respectively. Both cohorts received antagonists of the following receptors: D1/5 (SCH23390, SCH: 0.01, 0.02, 0.04 mg/kg) and D2/3 (raclopride, RAC 0.03, 0.10, 0.30 mg/kg) in consecutive balanced Latin square designs with flanking reference measurements. The antagonists were subsequently examined for effects on locomotor activity. RESULTS: SCH showed similar effects in both schedules, and the effects were reference-dependent in the vITI schedule. SCH reduced responding, but improved response accuracy, impulsivity, discriminability, and locomotor activity. RAC showed mixed effects on responsivity, but improved accuracy and discriminability. The discriminability improvement was driven by an increase in hit rate in the vITI schedule and a reduction in false alarm rate in the vSD schedule. RAC also decreased locomotor activity. CONCLUSION: Both D1/5 and D2/3 receptor antagonism reduced responding, but the outcome on discriminability differed, stemming from individual effects on hit and false alarm rate, and the weight of omissions within the calculation. The effects of SCH and RAC suggest that endogenous DA increases responding and impulsivity, but reduces accuracy and shows mixed effects on discriminability.


Assuntos
Antagonistas de Dopamina , Roedores , Camundongos , Animais , Feminino , Antagonistas de Dopamina/farmacologia , Camundongos Endogâmicos C57BL , Receptores de Dopamina D1 , Atenção , Comportamento Impulsivo , Antagonistas dos Receptores de Dopamina D2/farmacologia , Benzazepinas/farmacologia , Relação Dose-Resposta a Droga
19.
Psychopharmacology (Berl) ; 240(6): 1359-1372, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37129616

RESUMO

RATIONALE: The prepulse inhibition (PPI) of the startle reflex is the best-established index of sensorimotor gating. We documented that the neurosteroid allopregnanolone (AP) is necessary to reduce PPI in response to D1 dopamine receptor agonists. Since Sprague-Dawley (SD) rats are poorly sensitive to the PPI-disrupting effects of these drugs, we hypothesized that AP might increase this susceptibility. OBJECTIVES: We tested whether AP is sufficient to increase the vulnerability of SD rats to PPI deficits in response to the D1 receptor full agonist SKF82958. METHODS: SD rats were tested for PPI after treatment with SKF82958 (0.05-0.3 mg/kg, SC) in combination with either intraperitoneal (1-10 mg/kg) or intracerebral (0.5 µg/µl/side) AP administration into the medial prefrontal cortex (mPFC) or nucleus accumbens shell. To rule out potential confounds, we measured whether SKF82958 affected the endogenous mPFC levels of AP. RESULTS: SD rats exhibited marked PPI deficits in response to the combination of systemic and intra-mPFC AP with SKF82958 but not with the D2 receptor agonist quinpirole (0.3-0.6 mg/kg, SC). SKF82958 did not elevate mPFC levels of AP but enhanced the content of its precursor progesterone. The PPI deficits caused by SKF82958 in combination with AP were opposed by the AP antagonist isoallopregnanolone (10 mg/kg, IP) and the glutamate NMDA receptor positive modulator CIQ (5 mg/kg, IP). CONCLUSION: These results suggest that AP enables the detrimental effects of D1 receptor activation on sensorimotor gating. AP antagonism or glutamatergic modulation counters these effects and may have therapeutic potential for neuropsychiatric disorders characterized by gating deficits.


Assuntos
Pregnanolona , Receptores de Dopamina D1 , Ratos , Animais , Masculino , Ratos Sprague-Dawley , Pregnanolona/farmacologia , Benzazepinas/farmacologia , Reflexo de Sobressalto , Filtro Sensorial , Estimulação Acústica/métodos
20.
Int J Cancer ; 153(6): 1130-1138, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37165737

RESUMO

Aberrant epigenetic modifications are emerging as potent drivers of tumor initiation and progression. The deregulation of H3K27me3 marks has shown to play an important role in cancer progression in several cancers. The H3K27me3 mark is associated with gene silencing. The reversible nature of these epigenetic aberrations makes them an important target for treating cancer. GSK-J4 is a histone demethylase inhibitor that inhibits the JMJD3/UTX enzyme, which results in the upregulation of H3K27me3 levels. In this review, the anti-cancer properties of GSK-J4 have been summarized, the various molecular pathways targeted, in-vivo studies, and drug combination studies in different cancer models. GSK-J4 targeted pathways like apoptosis, cell cycle, invasion, migration, DNA damage repair, metabolism, oxidative stress, stemness, etc. GSK-J4 is a promising candidate alone and in combination with other conventional anti-cancer drugs against different cancer types.


Assuntos
Histona Desmetilases , Neoplasias , Humanos , Histona Desmetilases/metabolismo , Histonas/metabolismo , Benzazepinas/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo
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