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1.
IDCases ; 26: e01331, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34840952

RESUMEN

Among different pathogens, opportunistic viral infection caused by EBV is particularly relevant. This gammaherpesvirus, belonging to the Herpesviridae family, may complicate the disease course in different clinical settings by inducing pathological EBV pictures in patients with a defective immunologic response. Our report evaluated EBV-specific T cell responses by IFN- γ ELISPOT assay, which revealed defective EBV specific immunological response.

2.
Acta Cardiol ; 76(3): 307-311, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-32228163

RESUMEN

INTRODUCTION: The awareness of radiation doses and risks, also during interventional cardiology procedures, is essential today in order to apply the risk-benefit assessment and to reinforce the principles of justification and optimisation in clinical practice. METHODS: A voluntary survey with 10 questions and multiple-choice answers was run on a popular cardiology website (www.cardiolink.it) independently by a scientific publisher, in order to evaluate the contemporary level of radiation awareness in a multi-speciality sample of physicians in Italy. RESULTS: One thousand eight hundred and sixty-one physicians completed the test. The survey showed good results since both prescribers and practitioners (mostly cardiologists) working in Italy are largely aware of the cancer and non-cancer risks of medical radiation use, regardless of their subspecialty background. CONCLUSION: Physicians are largely aware of the cancer and non-cancer risks of medical radiation use, regardless of their subspecialty background. However, there is still broad space for improvement; in the future, the awareness of radiation risk is a prerequisite to create a culture of respect for radiation hazard and a commitment to minimise exposure and maximise protection.


Asunto(s)
Cardiología , Exposición Profesional , Humanos , Internet , Italia/epidemiología , Dosis de Radiación , Medición de Riesgo
3.
Dermatol Ther ; 33(6): e14044, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32697028

RESUMEN

This study assessed the effectiveness and safety of secukinumab in patients with moderate-severe psoriasis vulgaris in a real-world setting. A total of 120 patients (35.8% women; mean age 49.8 years) were enrolled. Mean PASI significantly decreased from 12.0 ± 6.6 at baseline to 4.7 ± 3.2 and 2.3 ± 4.0 at 3 and 12 months, respectively (P < .001). Patients with two or more lines of prior biological therapies had poorer persistence to therapy at 12 months (71%) vs those who were bio-naïve (93%) or patients with only one prior failure with a biological agent (88%) (log-rank = 9.33; P = .009). Multivariate regression analysis showed that patients beyond the second line of treatment had an increased risk of discontinuing secukinumab (HR: 3.6; 95% CI 1.3-10.2), while those without comorbidities had a lower risk (HR: 0.31; 95% CI 0.1-0.8). Our study confirms the effectiveness and safety of secukinumab in a real-life setting for psoriatic disease.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Psoriasis , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psoriasis/diagnóstico , Psoriasis/tratamiento farmacológico , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
4.
Artículo en Inglés | MEDLINE | ID: mdl-31952958

RESUMEN

Recently we reported that nucleus accumbens (NAcc) dopamine (DA) tracks uncertainty during operant responding for non-caloric saccharin. We also showed that repeated intermittent exposure to this uncertainty, like exposure to drugs of abuse, leads to sensitization of the locomotor and NAcc DA effects of amphetamine and promotes the subsequent self-administration of the drug. Here we review these findings together with others showing that NAcc glutamate signaling is similarly affected by uncertainty. Extracellular levels of glutamate in this site also track uncertainty in a task in which nose poking for saccharin on an escalating variable ratio schedule of reinforcement is associated with progressively increasing variance between performance of the operant and payout. Furthermore, sensitized behavioral responding to and for amphetamine following exposure to uncertainty is accompanied by increased levels of Ca2+/calmodulin-dependent protein kinase II (CaMKII) and protein kinase C (PKC) phosphorylation as well as altered protein levels of the transcription factor ∆FosB (increased) and glutamate transporter 1 (GLT1; decreased) in NAcc tissues. Notably, phosphorylation by CaMKII and PKC regulates AMPA receptor trafficking and function in this site, is elevated following psychostimulant exposure, and is necessary for the expression of enhanced drug taking. Increased ∆FosB and decreased GLT1 levels are observed following psychostimulant exposure, are associated with increased drug taking and seeking, and are known to modulate AMPA receptors and extracellular glutamate levels respectively. These adaptations in glutamate transmission as well as those observed with DA following repeated intermittent exposure to uncertainty are similar to those produced by exposure to abused drugs. Together, they point to the recruitment of both DA and glutamate signaling pathways in the NAcc in both drug and behavioral addictions. As uncertainty is central to games of chance, these findings have particular relevance for gambling disorders known to exhibit comorbidity with drug abuse.


Asunto(s)
Sensibilización del Sistema Nervioso Central/fisiología , Estimulantes del Sistema Nervioso Central/farmacología , Condicionamiento Operante/fisiología , Dopamina/metabolismo , Ácido Glutámico/metabolismo , Núcleo Accumbens/metabolismo , Incertidumbre , Animales , Humanos
5.
Curr Vasc Pharmacol ; 17(1): 92-98, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29345585

RESUMEN

BACKGROUND: Coronary Artery Calcifications (CACs) are associated with coronary atherosclerosis and Cardiovascular (CV) events. In "non-cardiovascular" settings, CACs can be easily detected on chest Multi-Detector Computed Tomography (MDCT). Their evaluation may help to better stratify CV risk in the general population, especially for primary prevention. AIMS: We retrospectively evaluated the relationship between CAC distribution and CV risk, determined by Framingham Risk Score (FRS), in a cohort of patients who underwent chest MDCT performed for several clinical indications. METHOD: We retrospectively recruited 305 patients (194 men, 111 women; mean age 70.5 years) from 3 different Italian centres. Patients with coronary stent, pacemaker and/or CV devices were excluded from the study. Circumflex Artery (LCX), Left Main Coronary Artery (LMCA), left Anterior Descending artery (LAD) and right coronary artery (RCA) were analysed. RESULTS: From a total population of 305 patients, 119 (39%) had low FRS (<10%), 115 (38%) had intermediate FRS (10-20%), and 71 (23%) had high FRS (>20%). The study identified 842 CACs located in decreasing order as follows: RCA (34.5%), LAD (32.3%), LCX (28%) and LMCA (13%). Statistical two-step analysis subdivided patients into two clusters according to FRS (risk threshold = 12.38%): cluster I (mean 9.34) and cluster II (mean 15.09). A significant association between CAC distribution and cluster II was demonstrated. CACs were mostly detected in patients with intermediate FRS. All patients (100%) with the highest CV risk showed intermediate RCA and LMCA involvement. CONCLUSION: Radiologists can note the distribution of CACs on a chest MDCT and should mandatorily record them in their reports. Depending on CAC presence and location, these findings may have important clinical implications, mostly in asymptomatic patients with intermediate FRS. This information may reclassify a patients' CV risk and improve clinical management.


Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Hallazgos Incidentales , Notificación Obligatoria , Tomografía Computarizada Multidetector , Radiografía Torácica/métodos , Calcificación Vascular/diagnóstico por imagen , Anciano , Enfermedades Asintomáticas , Enfermedad de la Arteria Coronaria/terapia , Femenino , Humanos , Italia , Masculino , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Calcificación Vascular/terapia
6.
Neuropsychopharmacology ; 44(2): 274-280, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29875447

RESUMEN

Prior exposure to abused drugs leads to long-lasting neuroadaptations culminating in excessive drug intake. Given the comorbidity between substance use and gambling disorders, surprisingly little is known about the effects of exposure to reinforcement contingencies experienced during games of chance. As it is a central feature of these games, we characterized the effects of exposure to uncertainty on biochemical and behavioral effects normally observed in rats exposed to amphetamine. Rats in different groups were trained to nose-poke for saccharin under certain [fixed-ratio (FR)] or uncertain conditions [variable-ratio (VR)] for 55 1-h sessions. Ratios were escalated on successive sessions and rats maintained on the last ratio (FR/VR 20) for 20-25 days. Two to three weeks later, rats were tested for their locomotor or nucleus accumbens dopamine (NAcc DA) response to amphetamine or self-administration of the drug using a lever press operant. NAcc DA overflow was also assessed in additional rats during the saccharin sessions. Rats exposed to uncertainty subsequently showed a higher locomotor and NAcc DA response to amphetamine and self-administered more drug infusions relative to rats exposed to predictable reinforcement. NAcc DA levels during the saccharin sessions tracked the variance of the scheduled ratios (a measure of uncertainty). VR rats showed escalating DA overflow with increasing ratios. Exposure to uncertainty triggered neuroadaptations similar to those produced by exposure to abused drugs. As these were produced in drug naive rats both during and after exposure to uncertainty, they provide a novel common pathway to drug and behavioral addictions.


Asunto(s)
Anfetamina/administración & dosificación , Estimulantes del Sistema Nervioso Central/administración & dosificación , Dopamina/metabolismo , Comportamiento de Búsqueda de Drogas/fisiología , Núcleo Accumbens/efectos de los fármacos , Sacarina/administración & dosificación , Animales , Masculino , Actividad Motora/efectos de los fármacos , Núcleo Accumbens/metabolismo , Ratas , Ratas Long-Evans , Esquema de Refuerzo , Autoadministración , Incertidumbre
7.
Mol Neurobiol ; 56(5): 3563-3575, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30151725

RESUMEN

The reinforcing effects of Δ9-tetrahydrocannabinol (THC) in rats and monkeys, and the reinforcement-related dopamine-releasing effects of THC in rats, can be attenuated by increasing endogenous levels of kynurenic acid (KYNA) through systemic administration of the kynurenine 3-monooxygenase inhibitor, Ro 61-8048. KYNA is a negative allosteric modulator of α7 nicotinic acetylcholine receptors (α7nAChRs) and is synthesized and released by astroglia, which express functional α7nAChRs and cannabinoid CB1 receptors (CB1Rs). Here, we tested whether these presumed KYNA autoreceptors (α7nAChRs) and CB1Rs regulate glutamate release. We used in vivo microdialysis and electrophysiology in rats, RNAscope in situ hybridization in brain slices, and primary culture of rat cortical astrocytes. Acute systemic administration of THC increased extracellular levels of glutamate in the nucleus accumbens shell (NAcS), ventral tegmental area (VTA), and medial prefrontal cortex (mPFC). THC also reduced extracellular levels of KYNA in the NAcS. These THC effects were prevented by administration of Ro 61-8048 or the CB1R antagonist, rimonabant. THC increased the firing activity of glutamatergic pyramidal neurons projecting from the mPFC to the NAcS or to the VTA in vivo. These effects were averted by pretreatment with Ro 61-8048. In vitro, THC elicited glutamate release from cortical astrocytes (on which we demonstrated co-localization of the CB1Rs and α7nAChR mRNAs), and this effect was prevented by KYNA and rimonabant. These results suggest a key role of astrocytes in interactions between the endocannabinoid system, kynurenine pathway, and glutamatergic neurotransmission, with ramifications for the pathophysiology and treatment of psychiatric and neurodegenerative diseases.


Asunto(s)
Astrocitos/metabolismo , Encéfalo/metabolismo , Dronabinol/toxicidad , Ácido Glutámico/metabolismo , Ácido Quinurénico/metabolismo , Recompensa , Potenciales de Acción/efectos de los fármacos , Animales , Astrocitos/efectos de los fármacos , Encéfalo/efectos de los fármacos , Células Cultivadas , Masculino , Núcleo Accumbens/efectos de los fármacos , Núcleo Accumbens/metabolismo , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas Sprague-Dawley , Receptor Cannabinoide CB1/genética , Receptor Cannabinoide CB1/metabolismo , Rimonabant/farmacología , Sulfonamidas/farmacología , Tiazoles/farmacología , Área Tegmental Ventral/efectos de los fármacos , Área Tegmental Ventral/metabolismo , Receptor Nicotínico de Acetilcolina alfa 7/genética , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo
9.
Artículo en Inglés | MEDLINE | ID: mdl-28675997

RESUMEN

BACKGROUND AND OBJECTIVE: The present review investigated cold-induced anaphylaxis, a potentially life-threatening condition that occurs after exposure to cold stimuli and is characterized by respiratory distress and/or hypotension. Anaphylaxis is rarely associated to cold-induced urticarial (CU), a particular form of physical urticaria that is difficult to diagnose and manage. The incidence of cold-induced urticaria has been estimated at about 0.05%, higher in colder regions and in women; its pathological mechanisms are still unknown. METHODS: The literature was searched via the Medline/PubMed database (http://www.ncbi.nlm.gov/ pubmed). RESULTS AND CONCLUSION: Patients affected by CU should be well-informed about the risk of anaphylaxis and preventive measures. The prevention of CU is based on the avoidance of cold exposure. The most effective treatment is antihistamines symptomatic therapy. Anyway, patients should also carry with them an emergency kit containing corticosteroids, antihistamines and an epinephrine injector. Future studies are necessary to determine the CU pathophysiology so to establish a more targeted management of this important and potentially life-threatening condition.


Asunto(s)
Anafilaxia/diagnóstico , Anafilaxia/etiología , Frío/efectos adversos , Urticaria/diagnóstico , Urticaria/etiología , Niño , Femenino , Humanos
10.
Neuropsychopharmacology ; 40(9): 2185-97, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25754762

RESUMEN

Inhibition of the enzyme fatty acid amide hydrolase (FAAH) counteracts reward-related effects of nicotine in rats, but it has not been tested for this purpose in non-human primates. Therefore, we studied the effects of the first- and second-generation O-arylcarbamate-based FAAH inhibitors, URB597 (cyclohexyl carbamic acid 3'-carbamoyl-3-yl ester) and URB694 (6-hydroxy-[1,1'-biphenyl]-3-yl-cyclohexylcarbamate), in squirrel monkeys. Both FAAH inhibitors: (1) blocked FAAH activity in brain and liver, increasing levels of endogenous ligands for cannabinoid and α-type peroxisome proliferator-activated (PPAR-α) receptors; (2) shifted nicotine self-administration dose-response functions in a manner consistent with reduced nicotine reward; (3) blocked reinstatement of nicotine seeking induced by reexposure to either nicotine priming or nicotine-associated cues; and (4) had no effect on cocaine or food self-administration. The effects of FAAH inhibition on nicotine self-administration and nicotine priming-induced reinstatement were reversed by the PPAR-α antagonist, MK886. Unlike URB597, which was not self-administered by monkeys in an earlier study, URB694 was self-administered at a moderate rate. URB694 self-administration was blocked by pretreatment with an antagonist for either PPAR-α (MK886) or cannabinoid CB1 receptors (rimonabant). In additional experiments in rats, URB694 was devoid of THC-like or nicotine-like interoceptive effects under drug-discrimination procedures, and neither of the FAAH inhibitors induced dopamine release in the nucleus accumbens shell--consistent with their lack of robust reinforcing effects in monkeys. Overall, both URB597 and URB694 show promise for the initialization and maintenance of smoking cessation because of their ability to block the rewarding effects of nicotine and prevent nicotine priming-induced and cue-induced reinstatement.


Asunto(s)
Benzamidas/farmacología , Carbamatos/farmacología , Oxigenasas de Función Mixta/antagonistas & inhibidores , Nicotina/administración & dosificación , Agonistas Nicotínicos/administración & dosificación , Recompensa , Animales , Compuestos de Bifenilo/farmacología , Encéfalo/efectos de los fármacos , Encéfalo/enzimología , Señales (Psicología) , Dopamina/metabolismo , Relación Dosis-Respuesta a Droga , Comportamiento de Búsqueda de Drogas/efectos de los fármacos , Extinción Psicológica/efectos de los fármacos , Masculino , Oxigenasas de Función Mixta/metabolismo , Modelos Animales , Ratas , Ratas Sprague-Dawley , Recurrencia , Saimiri , Autoadministración , Factores de Tiempo
11.
Nat Neurosci ; 16(11): 1652-61, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24121737

RESUMEN

In the reward circuitry of the brain, α-7-nicotinic acetylcholine receptors (α7nAChRs) modulate effects of Δ(9)-tetrahydrocannabinol (THC), marijuana's main psychoactive ingredient. Kynurenic acid (KYNA) is an endogenous negative allosteric modulator of α7nAChRs. Here we report that the kynurenine 3-monooxygenase (KMO) inhibitor Ro 61-8048 increases brain KYNA levels and attenuates cannabinoid-induced increases in extracellular dopamine in reward-related brain areas. In the self-administration model of drug abuse, Ro 61-8048 reduced the rewarding effects of THC and the synthetic cannabinoid WIN 55,212-2 in squirrel monkeys and rats, respectively, and it also prevented relapse to drug-seeking induced by reexposure to cannabinoids or cannabinoid-associated cues. The effects of enhancing endogenous KYNA levels with Ro 61-8048 were prevented by positive allosteric modulators of α7nAChRs. Despite a clear need, there are no medications approved for treatment of marijuana dependence. Modulation of KYNA offers a pharmacological strategy for achieving abstinence from marijuana and preventing relapse.


Asunto(s)
Encéfalo/metabolismo , Ácido Quinurénico/metabolismo , Trastornos Relacionados con Sustancias , Analgésicos/administración & dosificación , Animales , Benzoxazinas/administración & dosificación , Agonistas de Receptores de Cannabinoides/farmacología , Condicionamiento Operante/efectos de los fármacos , Señales (Psicología) , Discriminación en Psicología/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Dronabinol/farmacología , Comportamiento de Búsqueda de Drogas/efectos de los fármacos , Masculino , Memoria a Corto Plazo/efectos de los fármacos , Morfolinas/administración & dosificación , Naftalenos/administración & dosificación , Ratas , Ratas Long-Evans , Ratas Sprague-Dawley , Refuerzo en Psicología , Saimiri , Prevención Secundaria , Autoadministración , Trastornos Relacionados con Sustancias/tratamiento farmacológico , Trastornos Relacionados con Sustancias/metabolismo , Trastornos Relacionados con Sustancias/patología , Sulfonamidas/farmacología , Tiazoles/farmacología , Factores de Tiempo , Vigilia
12.
Neuropsychopharmacology ; 37(8): 1838-47, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22453137

RESUMEN

Experimental drugs that activate α-type peroxisome proliferator-activated receptors (PPARα) have recently been shown to reduce the rewarding effects of nicotine in animals, but these drugs have not been approved for human use. The fibrates are a class of PPARα-activating medications that are widely prescribed to improve lipid profiles and prevent cardiovascular disease, but these drugs have not been tested in animal models of nicotine reward. Here, we examine the effects of clofibrate, a representative of the fibrate class, on reward-related behavioral, electrophysiological, and neurochemical effects of nicotine in rats and squirrel monkeys. Clofibrate prevented the acquisition of nicotine-taking behavior in naive animals, substantially decreased nicotine taking in experienced animals, and counteracted the relapse-inducing effects of re-exposure to nicotine or nicotine-associated cues after a period of abstinence. In the central nervous system, clofibrate blocked nicotine's effects on neuronal firing in the ventral tegmental area and on dopamine release in the nucleus accumbens shell. All of these results suggest that fibrate medications might promote smoking cessation. The fact that fibrates are already approved for human use could expedite clinical trials and subsequent implementation of fibrates as a treatment for tobacco dependence, especially in smokers with abnormal lipid profiles.


Asunto(s)
Clofibrato/farmacología , Evaluación Preclínica de Medicamentos/psicología , Hipolipemiantes/farmacología , Nicotina/farmacología , Recompensa , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/fisiología , Animales , Clofibrato/uso terapéutico , Modelos Animales de Enfermedad , Dopamina/metabolismo , Evaluación Preclínica de Medicamentos/métodos , Indoles/farmacología , Masculino , Neuronas/fisiología , Nicotina/administración & dosificación , Nicotina/antagonistas & inhibidores , Núcleo Accumbens/efectos de los fármacos , Núcleo Accumbens/metabolismo , PPAR alfa/agonistas , PPAR alfa/antagonistas & inhibidores , Ratas , Ratas Sprague-Dawley , Saimiri , Prevención Secundaria , Autoadministración , Tabaquismo/tratamiento farmacológico , Área Tegmental Ventral/efectos de los fármacos , Área Tegmental Ventral/fisiología
13.
Br J Pharmacol ; 165(8): 2539-48, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21557729

RESUMEN

BACKGROUND AND PURPOSE: The fatty acid amide hydrolase inhibitor URB597 can reverse the abuse-related behavioural and neurochemical effects of nicotine in rats. Fatty acid amide hydrolase inhibitors block the degradation (and thereby magnify and prolong the actions) of the endocannabinoid anandamide (AEA), and also the non-cannabinoid fatty acid ethanolamides oleoylethanolamide (OEA) and palmitoylethanolamide (PEA). OEA and PEA are endogenous ligands for peroxisome proliferator-activated receptors alpha (PPAR-α). Since recent evidence indicates that PPAR-α can modulate nicotine reward, it is unclear whether AEA plays a role in the effects of URB597 on nicotine reward. EXPERIMENTAL APPROACH: A way to selectively increase endogenous levels of AEA without altering OEA or PEA levels is to inhibit AEA uptake into cells by administering the AEA transport inhibitor N-(4-hydroxyphenyl)-arachidonamide (AM404). To clarify AEA's role in nicotine reward, we investigated the effect of AM404 on conditioned place preference (CPP), reinstatement of abolished CPP, locomotor suppression and anxiolysis in an open field, and dopamine elevations in the nucleus accumbens shell induced by nicotine in Sprague-Dawley rats. KEY RESULTS: AM404 prevented the development of nicotine-induced CPP and impeded nicotine-induced reinstatement of the abolished CPP. Furthermore, AM404 reduced nicotine-induced increases in dopamine levels in the nucleus accumbens shell, the terminal area of the brain's mesolimbic reward system. AM404 did not alter the locomotor suppressive or anxiolytic effect of nicotine. CONCLUSIONS AND IMPLICATIONS: These findings suggest that AEA transport inhibition can counteract the addictive effects of nicotine and that AEA transport may serve as a new target for development of medications for treatment of tobacco dependence. LINKED ARTICLES: This article is part of a themed section on Cannabinoids in Biology and Medicine. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.165.issue-8. To view Part I of Cannabinoids in Biology and Medicine visit http://dx.doi.org/10.1111/bph.2011.163.issue-7.


Asunto(s)
Ácidos Araquidónicos/antagonistas & inhibidores , Ácidos Araquidónicos/uso terapéutico , Conducta Adictiva/tratamiento farmacológico , Nicotina/farmacología , Núcleo Accumbens/efectos de los fármacos , Alcamidas Poliinsaturadas/antagonistas & inhibidores , Animales , Ácidos Araquidónicos/farmacología , Ácidos Araquidónicos/fisiología , Conducta Adictiva/fisiopatología , Conducta Animal/efectos de los fármacos , Condicionamiento Psicológico/fisiología , Dopamina/metabolismo , Dronabinol/farmacología , Endocannabinoides , Masculino , Actividad Motora/efectos de los fármacos , Agonistas Nicotínicos/farmacología , Núcleo Accumbens/fisiología , Ratas , Ratas Sprague-Dawley , Recompensa
14.
Biol Psychiatry ; 69(7): 633-41, 2011 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-20801430

RESUMEN

BACKGROUND: Recent findings indicate that inhibitors of fatty acid amide hydrolase (FAAH) counteract the rewarding effects of nicotine in rats. Inhibition of FAAH increases levels of several endogenous substances in the brain, including the endocannabinoid anandamide and the noncannabinoid fatty acid ethanolamides oleoylethanolamide (OEA) and palmitoylethanolamide, which are ligands for alpha-type peroxisome proliferator-activated nuclear receptors (PPAR-α). Here, we evaluated whether directly acting PPAR-α agonists can modulate reward-related effects of nicotine. METHODS: We combined behavioral, neurochemical, and electrophysiological approaches to evaluate effects of the PPAR-α agonists [[4-Chloro-6-[(2,3-dimethylphenyl)amino]-2-pyrimidinyl]thio]acetic acid (WY14643) and methyl oleoylethanolamide (methOEA; a long-lasting form of OEA) on 1) nicotine self-administration in rats and squirrel monkeys; 2) reinstatement of nicotine-seeking behavior in rats and monkeys; 3) nicotine discrimination in rats; 4) nicotine-induced electrophysiological activity of ventral tegmental area dopamine neurons in anesthetized rats; and 5) nicotine-induced elevation of dopamine levels in the nucleus accumbens shell of freely moving rats. RESULTS: The PPAR-α agonists dose-dependently decreased nicotine self-administration and nicotine-induced reinstatement in rats and monkeys but did not alter food- or cocaine-reinforced operant behavior or the interoceptive effects of nicotine. The PPAR-α agonists also dose-dependently decreased nicotine-induced excitation of dopamine neurons in the ventral tegmental area and nicotine-induced elevations of dopamine levels in the nucleus accumbens shell of rats. The ability of WY14643 and methOEA to counteract the behavioral, electrophysiological, and neurochemical effects of nicotine was reversed by the PPAR-α antagonist 1-[(4-Chlorophenyl)methyl]-3-[(1,1-dimethylethyl)thio]-a,a-dimethyl-5-(1-methylethyl)-1H-Indole-2-propanoic acid (MK886). CONCLUSIONS: These findings indicate that PPAR-α might provide a valuable new target for antismoking medications.


Asunto(s)
Nicotina/administración & dosificación , Agonistas Nicotínicos/administración & dosificación , PPAR alfa/metabolismo , Refuerzo en Psicología , Recompensa , Potenciales de Acción/efectos de los fármacos , Animales , Conducta Animal/efectos de los fármacos , Condicionamiento Operante/efectos de los fármacos , Dopamina/metabolismo , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Inhibidores Enzimáticos/farmacología , Indoles/farmacología , Masculino , Microdiálisis/métodos , Neuronas/efectos de los fármacos , Núcleo Accumbens/efectos de los fármacos , Núcleo Accumbens/metabolismo , Oligosacáridos/farmacología , Proliferadores de Peroxisomas/farmacología , Pirimidinas/farmacología , Ratas , Ratas Sprague-Dawley , Saimiri , Autoadministración , Área Tegmental Ventral/citología
15.
Addict Biol ; 16(3): 405-15, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21054689

RESUMEN

Several recent studies suggest functional and molecular interactions between striatal adenosine A(2A) and cannabinoid CB(1) receptors. Here, we demonstrate that A(2A) receptors selectively modulate reinforcing effects of cannabinoids. We studied effects of A(2A) receptor blockade on the reinforcing effects of delta-9-tetrahydrocannabinol (THC) and the endogenous CB(1) receptor ligand anandamide under a fixed-ratio schedule of intravenous drug injection in squirrel monkeys. A low dose of the selective adenosine A(2A) receptor antagonist MSX-3 (1 mg/kg) caused downward shifts of THC and anandamide dose-response curves. In contrast, a higher dose of MSX-3 (3 mg/kg) shifted THC and anandamide dose-response curves to the left. MSX-3 did not modify cocaine or food pellet self-administration. Also, MSX-3 neither promoted reinstatement of extinguished drug-seeking behavior nor altered reinstatement of drug-seeking behavior by non-contingent priming injections of THC. Finally, using in vivo microdialysis in freely-moving rats, a behaviorally active dose of MSX-3 significantly counteracted THC-induced, but not cocaine-induced, increases in extracellular dopamine levels in the nucleus accumbens shell. The significant and selective results obtained with the lower dose of MSX-3 suggest that adenosine A(2A) antagonists acting preferentially at presynaptic A(2A) receptors might selectively reduce reinforcing effects of cannabinoids that lead to their abuse. However, the appearance of potentiating rather than suppressing effects on cannabinoid reinforcement at the higher dose of MSX-3 would likely preclude the use of such a compound as a medication for cannabis abuse. Adenosine A(2A) antagonists with more selectivity for presynaptic versus postsynaptic receptors could be potential medications for treatment of cannabis abuse.


Asunto(s)
Antagonistas del Receptor de Adenosina A2/farmacología , Ácidos Araquidónicos/farmacología , Moduladores de Receptores de Cannabinoides/farmacología , Cocaína/farmacología , Dronabinol/farmacología , Alcamidas Poliinsaturadas/farmacología , Psicotrópicos/farmacología , Receptor de Adenosina A2A/efectos de los fármacos , Receptor Cannabinoide CB1/agonistas , Xantinas/farmacología , Animales , Cuerpo Estriado/efectos de los fármacos , Dopamina/metabolismo , Relación Dosis-Respuesta a Droga , Endocannabinoides , Inyecciones Intravenosas , Masculino , Abuso de Marihuana/fisiopatología , Abuso de Marihuana/rehabilitación , Microdiálisis , Núcleo Accumbens/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Receptores Presinapticos/efectos de los fármacos , Refuerzo en Psicología , Saimiri , Autoadministración
16.
Neuropsychopharmacology ; 35(8): 1751-60, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20357760

RESUMEN

Nicotine is the main psychoactive ingredient in tobacco and its rewarding effects are considered primarily responsible for persistent tobacco smoking and relapse. Although dopamine has been extensively implicated in the rewarding effects of nicotine, noradrenergic systems may have a larger role than previously suspected. This study evaluated the role of noradrenergic alpha(1) receptors in nicotine and food self-administration and relapse, nicotine discrimination, and nicotine-induced dopamine release in the nucleus accumbens in rats. We found that the noradrenergic alpha(1) receptor antagonist prazosin (0.25-1 mg/kg) dose dependently reduced the self-administration of nicotine (0.03 mg/kg), an effect that was maintained over consecutive daily sessions; but did not reduce food self-administration. Prazosin also decreased reinstatement of extinguished nicotine seeking induced by either a nicotine prime (0.15 mg/kg) or nicotine-associated cues, but not food-induced reinstatement of food-seeking, and decreased nicotine-induced (0.15 mg/kg) dopamine release in the nucleus accumbens shell. However, prazosin did not have nicotine-like discriminative effects and did not alter the dose-response curve for nicotine discrimination. These findings suggest that stimulation of noradrenergic alpha(1) receptors is involved in nicotine self-administration and relapse, possibly via facilitation of nicotine-induced activation of the mesolimbic dopaminergic system. The findings point to alpha(1) adrenoceptor blockade as a potential new approach to the treatment of tobacco dependence in humans.


Asunto(s)
Antagonistas Adrenérgicos alfa/uso terapéutico , Receptores Adrenérgicos alfa 1/metabolismo , Tabaquismo/tratamiento farmacológico , Tabaquismo/metabolismo , Antagonistas de Receptores Adrenérgicos alfa 1 , Antagonistas Adrenérgicos alfa/farmacología , Análisis de Varianza , Animales , Condicionamiento Operante/efectos de los fármacos , Señales (Psicología) , Discriminación en Psicología/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Preferencias Alimentarias/efectos de los fármacos , Microdiálisis/métodos , Nicotina/administración & dosificación , Agonistas Nicotínicos/administración & dosificación , Prazosina/uso terapéutico , Ratas , Ratas Long-Evans , Ratas Sprague-Dawley , Esquema de Refuerzo , Refuerzo en Psicología , Autoadministración/métodos , Tabaquismo/psicología
17.
Biol Psychiatry ; 63(3): 286-92, 2008 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-17920565

RESUMEN

BACKGROUND: The recreational drug, Salvinorin A, derived from the plant of Salvia divinorum, is a potent and selective kappa-opioid receptor agonist. The abuse of selective k-agonists is a novel phenomenon, the mechanism of which is not fully understood. METHODS: We investigated salvinorin A given SC on the conditioned place preference (.05-160 microg/kg) and intracerebroventricular (ICV) self-administration (.01-1 microg/infusion) paradigms, in Wistar rats. RESULTS: The present results demonstrate the rewarding effects of Salvinorin A in a range of doses between .1 and 40 microg/kg SC for conditioned place preference test and .1-.5 microg/infusion for ICV self-administration. Highest doses (160 microg/kg for conditioned place preference test and 1 microg/infusion for ICV self-administration) were aversive. The rewarding effect was antagonized by intraperitoneal (IP) pretreatment with the cannabinoid CB(1) receptor antagonist, rimonabant [N-piperidino-5-(4-chlorophenyl)1-(2,4-dichloro phenyl)-4 methyl pyrazole 3-carboxamide] (1 mg/kg), and the kappa-opioid receptor antagonist, nor-binaltorphimine (nor-BNI) (10 mg/kg). In the shell of nucleus accumbens, dopamine extracellular levels were increased after administration of salvinorin A (40 microg/kg SC), reaching a maximum value of about 150%. CONCLUSIONS: These data provide the demonstration of the rewarding effects of Salvinorin A through an interaction between kappa-opioid and (endo)cannabinoid system in rats.


Asunto(s)
Antioxidantes/farmacología , Moduladores de Receptores de Cannabinoides/fisiología , Condicionamiento Operante/efectos de los fármacos , Diterpenos/farmacología , Endocannabinoides , Receptores Opioides kappa/fisiología , Recompensa , Análisis de Varianza , Animales , Conducta Animal/efectos de los fármacos , Moduladores de Receptores de Cannabinoides/antagonistas & inhibidores , Diterpenos de Tipo Clerodano , Dopamina/metabolismo , Relación Dosis-Respuesta a Droga , Vías de Administración de Medicamentos , Interacciones Farmacológicas , Masculino , Microdiálisis/métodos , Actividad Motora/efectos de los fármacos , Naltrexona/análogos & derivados , Naltrexona/farmacología , Antagonistas de Narcóticos/farmacología , Piperidinas/farmacología , Pirazoles/farmacología , Ratas , Ratas Wistar , Rimonabant , Autoadministración
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