RESUMEN
A number of para-substituted benzoic acids (p-BA) and chemicals metabolized to p-BA have been found to confer adverse effects in male rats on sperm viability, motility, and morphology. These effects are putatively associated with the metabolism of p-BA to toxic intermediates. We had shown that p-BA lead to accumulation of high levels of p-alkyl-benzoyl-CoA conjugates in plated primary rat hepatocytes. Here we further investigated the relevance of this metabolic pathway for the reprotoxic effects in rats and rabbits. We extended the structure-activity relationship to a set of 19 chemicals (nine reprotoxic and ten non-reprotoxic) and confirmed a very strong correlation between p-alkyl-benzoyl-CoA accumulation in rat hepatocytes and the toxic outcome. Species specificity was probed by comparing rat, rabbit and human hepatocytes, and p-benzoyl-CoA accumulation was found to be specific to the rat hepatocytes, not occurring in human hepatocytes. There was also very limited accumulation in hepatocytes from rabbits that are a non-responder species in in vivo studies. Tissues of rats treated with 3-(4-isopropylphenyl)-2-methylpropanal were analysed and p-isopropyl-benzoyl-CoA conjugates were detected in the liver and in the testes in animals at toxic doses indicating that the metabolism observed in vitro is relevant to the in vivo situation and the critical metabolite does also occur in the reproductive tissue. These multiple lines of evidence further support benzoyl-CoA accumulation as a key initiating event for a specific group of male reproductive toxicants, and indicate a species-specific effect in the rat.
Asunto(s)
Acilcoenzima A/toxicidad , Benzoatos/toxicidad , Hepatocitos/efectos de los fármacos , Reproducción/efectos de los fármacos , Testículo/efectos de los fármacos , Acilcoenzima A/metabolismo , Animales , Benzoatos/metabolismo , Biotransformación , Células Cultivadas , Hepatocitos/metabolismo , Humanos , Masculino , Estructura Molecular , Conejos , Ratas Sprague-Dawley , Medición de Riesgo , Factores Sexuales , Especificidad de la Especie , Relación Estructura-Actividad , Testículo/metabolismo , Pruebas de ToxicidadRESUMEN
11ß-Hydroxysteroid dehydrogenase type 1 (11ß-HSD1) is considered a potential therapeutic target in the treatment of type 2 diabetes mellitus. In this study, we investigated the pharmacological properties of HIS-388 (N-[(1R,2s,3S,5s,7s)-5-hydroxyadamantan-2-yl]-3-(pyridin-2-yl) isoxazole-4-carboxamide), a newly synthesized 11ß-HSD1 inhibitor, using several mouse models. In cortisone pellet-implanted mice in which hypercortisolism and hyperinsulinemia occur, single administration of HIS-388 exhibited potent and prolonged suppression of plasma cortisol and lowered plasma insulin levels. These effects were more potent than those achieved using the same dose of other 11ß-HSD1 inhibitors (carbenoxolone and compound 544 [3-[(1s,3s)-adamantan-1-yl]-6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepine]), indicating that HIS-388 potently and continuously suppresses 11ß-HSD1 enzyme activity in vivo. In diet-induced obese mice, HIS-388 significantly decreased fasting blood glucose, plasma insulin concentration, and homeostasis model assessment-insulin resistance score, and ameliorated insulin sensitivity. In addition, HIS-388 significantly reduced body weight and suppressed the elevation of blood glucose during the pyruvate tolerance test. In nongenetic type 2 diabetic mice with disease induced by a high-fat diet and low-dose streptozotocin, HIS-388 also significantly decreased postprandial blood glucose and plasma insulin levels and improved glucose intolerance. The effects of HIS-388 on glucose metabolism were indistinguishable from those of an insulin sensitizer, pioglitazone. Our results suggest that HIS-388 is a potent agent against type 2 diabetes. Moreover, amelioration of diabetic symptoms by HIS-388 was at least in part attributable to an antiobesity effect or improvement of hepatic insulin resistance. Therefore, potent and long-lasting inhibition of 11ß-HSD1 enzyme activity may be an effective approach for the treatment of type 2 diabetes and obesity-associated disease.
Asunto(s)
11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/antagonistas & inhibidores , Adamantano/análogos & derivados , Diabetes Mellitus Experimental/tratamiento farmacológico , Inhibidores Enzimáticos/uso terapéutico , Intolerancia a la Glucosa , Hipoglucemiantes/uso terapéutico , Resistencia a la Insulina , Isoxazoles/farmacología , Obesidad/tratamiento farmacológico , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/metabolismo , Adamantano/farmacología , Adamantano/uso terapéutico , Administración Oral , Animales , Azepinas/uso terapéutico , Carbenoxolona/uso terapéutico , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/farmacología , Femenino , Humanos , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/farmacología , Isoxazoles/uso terapéutico , Masculino , Ratones , Ratones Endogámicos C57BL , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/enzimología , Pioglitazona , Tiazolidinedionas/uso terapéutico , Triazoles/uso terapéuticoRESUMEN
BACKGROUND: MicroRNAs (miRNAs) are important in hepatic pathophysiology and the development of liver cancer. OBJECTIVE: To explore miRNAs that are regulated with the progression of liver fibrosis caused by chronic liver disease. DESIGN: The regulated miRNAs in human livers infected with hepatitis C virus were identified by microarray analysis. Their expression in human livers with non-alcoholic steatohepatitis, mouse livers from two fibrosis models and cultured stellate cells was validated by real-time RT-PCR. The regulation of miR-222 expression in stellate cells by nuclear factor kappa B (NF-κB) was assayed. Finally, the effects of an miR-222 precursor or inhibitor on the expression of cyclin-dependent kinase inhibitor 1B (CDKN1B) and the growth of LX-2 cells were determined. RESULTS: It was found that miR-199a-5p/199a-3p and miR-221/222 were upregulated in the human liver in a fibrosis progression-dependent manner. Among these miRNAs, miR-221/222 were upregulated in LX-2 cells and increased during the course of culture-dependent activation of mouse primary stellate cells, in a manner similar to the expression of α1(I) collagen and α-smooth muscle actin mRNAs. The expression of miR-221/222 increased in mouse models of liver fibrosis. In contrast, an NF-κB inhibitor significantly suppressed the miR-222 induction that was stimulated in culture by transforming growth factor α or tumour necrosis factor α. Although overexpression or downregulation of miR-222 failed to regulate the growth of LX-2 cells, miR-222 bound to the CDKN1B 3'UTR and regulated the expression of the corresponding protein. CONCLUSION: miR-221/222 may be new markers for stellate cell activation and liver fibrosis progression.
Asunto(s)
Regulación de la Expresión Génica , Células Estrelladas Hepáticas/metabolismo , Cirrosis Hepática/genética , Cirrosis Hepática/patología , MicroARNs/metabolismo , Anciano , Animales , Biopsia con Aguja , Estudios de Casos y Controles , Proliferación Celular , Células Cultivadas , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Femenino , Marcadores Genéticos , Humanos , Inmunohistoquímica , Cirrosis Hepática/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Distribución Aleatoria , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Estadísticas no Paramétricas , Análisis de Matrices Tisulares , Regulación hacia ArribaRESUMEN
Cytoglobin (Cygb) is a recently discovered vertebrate globin with molecular characteristics that are similar to myoglobin. To study the biological function of Cygb in vivo, we generated Cygb knockout mice and investigated their susceptibility to N,N-diethylnitrosamine (DEN)-induced tumorigenesis. Four-week-old male mice were administered DEN in drinking water at a dose of 25 ppm for 25 weeks or 0.05 ppm for 36 weeks. Cygb deficiency promoted the DEN-induced development of liver and lung tumors. All Cygb(+/-) and Cygb(-/-) mice treated with 25-ppm DEN exhibited liver tumors, compared with 44.4% of their wild-type counterparts. Lung tumors were present only in Cygb-deficient mice. More than 40% of Cygb(-/-) mice developed liver and lung tumors at the nontoxic dose of DEN (0.05 ppm), which did not induce tumors in wild-type mice. Cygb loss was associated with increased cancer cell proliferation, elevated extracellular signal-regulated kinase and Akt activation, overexpression of IL-1ß, IL-6, Tnfα, and Tgfß3 mRNAs, and hepatic collagen accumulation. Cygb-deficient mice also exhibited increased nitrotyrosine formation and dysregulated expression of cancer-related genes (cyclin D2, p53, Pak1, Src, Cdkn2a, and Cebpa). These results suggest that Cygb deficiency induces susceptibility to cancer development in the liver and lungs of mice exposed to DEN. Thus, globins such as Cygb will shed new light on the biological features of organ carcinogenesis.
Asunto(s)
Dietilnitrosamina/farmacología , Globinas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Pulmonares/metabolismo , Alquilantes/farmacología , Animales , Proliferación Celular , Citoglobina , Relación Dosis-Respuesta a Droga , Exones , Femenino , Regulación Neoplásica de la Expresión Génica , Vectores Genéticos , Globinas/metabolismo , Neoplasias Hepáticas/inducido químicamente , Neoplasias Pulmonares/inducido químicamente , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Modelos GenéticosRESUMEN
We report the discovery and structure-activity relationship of 2,6-disubstituted pyrazines, which are potent and selective CK2 inhibitors. Lead compound 1 was identified, and derivatives were prepared to develop potent inhibitory activity. As a result, we obtained compound 7, which was the smallest unit that retained potency. Then, introducing an aminoalkyl group at the 6-position of the indazole ring resulted in improved efficacy in both enzymatic and cell-based CK2 inhibition assays. Moreover, compound 13 showed selectivity against other kinases and in vivo efficacy in a rat nephritis model. These results show that 2,6-disubstituted pyrazines have potential as therapeutic agents for nephritis.
Asunto(s)
Quinasa de la Caseína II/antagonistas & inhibidores , Indazoles/química , Inhibidores de Proteínas Quinasas/química , Pirazinas/química , Animales , Sitios de Unión , Quinasa de la Caseína II/metabolismo , Simulación por Computador , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Humanos , Indazoles/síntesis química , Indazoles/uso terapéutico , Inyecciones Intraperitoneales , Nefritis/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/uso terapéutico , Estructura Terciaria de Proteína , Pirazinas/síntesis química , Pirazinas/uso terapéutico , Ratas , Relación Estructura-ActividadRESUMEN
Recent studies have suggested that interferons (IFNs) have an antifibrotic effect in the liver independent of their antiviral effect although its detailed mechanism remains largely unknown. Some microRNAs have been reported to regulate pathophysiological activities of hepatic stellate cells (HSCs). We performed analyses of the antiproliferative effects of IFNs in HSCs with special regard to microRNA-195 (miR-195). We found that miR-195 was prominently down-regulated in the proliferative phase of primary-cultured mouse HSCs. Supporting this fact, IFN-ß induced miR-195 expression and inhibited the cell proliferation by delaying their G1 to S phase cell cycle progression in human HSC line LX-2. IFN-ß down-regulated cyclin E1 and up-regulated p21 mRNA levels in LX-2 cells. Luciferase reporter assay revealed the direct interaction of miR-195 with the cyclin E1 3'UTR. Overexpression of miR-195 lowered cyclin E1 mRNA and protein expression levels, increased p21 mRNA and protein expression levels, and inhibited cell proliferation in LX-2 cells. Moreover miR-195 inhibition restored cyclin E1 levels that were down-regulated by IFN-ß. In conclusion, IFN-ß inhibited the proliferation of LX-2 cells by delaying cell cycle progression in G1 to S phase, partially through the down-regulation of cyclin E1 and up-regulation of p21. IFN-induced miR-195 was involved in these processes. These observations reveal a new mechanistic aspect of the antifibrotic effect of IFNs in the liver.
Asunto(s)
Proliferación Celular , Ciclina E/antagonistas & inhibidores , Ciclina E/biosíntesis , Regulación hacia Abajo/fisiología , Inhibidores de Crecimiento/fisiología , Células Estrelladas Hepáticas/citología , Interferón beta/fisiología , MicroARNs/fisiología , Proteínas Oncogénicas/antagonistas & inhibidores , Proteínas Oncogénicas/biosíntesis , Animales , Línea Celular , Ciclina E/genética , Regulación hacia Abajo/genética , Fase G1/genética , Fase G1/fisiología , Inhibidores de Crecimiento/genética , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs/biosíntesis , MicroARNs/genética , Proteínas Oncogénicas/genética , Fase S/genética , Fase S/fisiologíaRESUMEN
MicroRNAs (miRNAs) participate in the regulation of cellular functions including proliferation, apoptosis, and migration. It has been previously shown that the miR-29 family is involved in regulating type I collagen expression by interacting with the 3'UTR of its mRNA. Here, we investigated the roles of miR-29b in the activation of mouse primary-cultured hepatic stellate cells (HSCs), a principal collagen-producing cell in the liver. Expression of miR-29b was found to be down-regulated during HSC activation in primary culture. Transfection of a miR-29b precursor markedly attenuated the expression of Col1a1 and Col1a2 mRNAs and additionally blunted the increased expression of α-SMA, DDR2, FN1, ITGB1, and PDGFR-ß, which are key genes involved in the activation of HSCs. Further, overexpression of miR-29b led HSCs to remain in a quiescent state, as evidenced by their quiescent star-like cell morphology. Although phosphorylation of FAK, ERK, and Akt, and the mRNA expression of c-jun was unaffected, miR-29b overexpression suppressed the expression of c-fos mRNA. These results suggested that miR-29b is involved in the activation of HSCs and could be a candidate molecule for suppressing their activation and consequent liver fibrosis.
Asunto(s)
Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/patología , Cirrosis Hepática , MicroARNs/metabolismo , Actinas/genética , Animales , Colágeno Tipo I/genética , Cadena alfa 1 del Colágeno Tipo I , Receptores con Dominio Discoidina , Fibronectinas/genética , Integrina beta1/genética , Cirrosis Hepática/genética , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Masculino , Ratones , Ratones Endogámicos C57BL , MicroARNs/genética , ARN Mensajero/biosíntesis , Proteínas Tirosina Quinasas Receptoras/genética , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Receptores Mitogénicos/genéticaRESUMEN
BACKGROUND: Platelet-neutrophil complexes (PNCs) readily migrate into tissues and induce tissue damage via cytokine or other pathogenic factors release. These actions are involved in onset and progression of acute respiratory distress syndrome (ARDS). Thus, simultaneous removal of cytokines and activated neutrophils, including PNCs by blood purification may prevent development of ARDS and enhance drug effects. The goal of this study was to examine the effect of a newly developed adsorption column (NOA-001) that eliminates cytokines and activated neutrophils in a lung injury model. RESULTS: Adsorption of cytokines, such as IL-8, IL-6 and HMGB-1, and PNCs was first measured in vitro. Lung injury was induced by HCl and lipopolysaccharide intratracheal infusion in rabbits ventilated at a low tidal volume (7-8 mL/kg) and PEEP (2.5 cmH2O) for lung protection. Arterial blood gas, hematologic values, plasma IL-8, blood pressure and heart rate were measured, and lung damage was evaluated histopathologically in animals treated with 8-h direct hemoperfusion with or without use of NOA-001. The in vitro adsorption rates for IL-8, IL-6, HMGB-1, activated granulocytes and PNCs were 99.5 (99.4-99.5)%, 63.9 (63.4-63.9)%, 57.6 (57.4-62.1)%, 9.9 (-4.4-21.3)% and 60.9 (49.0-67.6)%, respectively. Absorption of PNCs onto fibers was confirmed microscopically. These adsorption effects were associated with several improvements in the rabbit model. In respiratory function, the PaO2/FIO2 ratios at 8 h were 314 ± 55 mmHg in the NOA-001 group and 134 ± 41 mmHg in the sham group. The oxygenation index and PaCO2 at 8 h were 9.6 ± 3.1 and 57.0 ± 9.6 mmHg in the sham group and 3.0 ± 0.8 and 40.4 ± 4.5 mmHg in the NOA-001 group, respectively (p < 0.05). Blood pH at 8 h reached 7.18 ± 0.06 in the sham group, but was maintained at 7.36 ± 0.03 (within the normal range) in the NOA-001 group (p < 0.05). In lung histopathology, fewer hyaline membrane and inflammatory cells were observed in the NOA-001 group. CONCLUSION: A column for simultaneous removal of cytokines and PNCs showed efficacy for improvement of pulmonary function in an animal model. This column may be effective in support of treatment of ARDS.
RESUMEN
MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expression through imperfect base pairing with the 3' untranslated region (3'UTR) of target mRNA. We studied the regulation of alpha 1 (I) collagen (Col1A1) expression by miRNAs in human stellate cells, which are involved in liver fibrogenesis. Among miR-29b, -143, and -218, whose expressions were altered in response to transforming growth factor-beta1 or interferon-alpha stimulation, miR-29b was the most effective suppressor of type I collagen at the mRNA and protein level via its direct binding to Col1A1 3'UTR. miR-29b also had an effect on SP1 expression. These results suggested that miR-29b is involved in the regulation of type I collagen expression by interferon-alpha in hepatic stellate cells. It is anticipated that miR-29b will be used for the regulation of stellate cell activation and lead to antifibrotic therapy.
Asunto(s)
Colágeno Tipo I/genética , Regulación de la Expresión Génica , Células Estrelladas Hepáticas/metabolismo , MicroARNs/metabolismo , Regiones no Traducidas 3' , Células Cultivadas , Cadena alfa 1 del Colágeno Tipo I , Humanos , Interferón-alfa/metabolismo , Factor de Transcripción Sp1/genéticaRESUMEN
There is a body of evidence implying the involvement of the central glutamatergic system in morphine dependence. In this study, we examined the effect of intracerebroventricular (i.c.v.) administration of a potent glutamate transporter inhibitor, DL-threo-beta-benzyloxyaspartate (DL-TBOA), on acute morphine-induced antinociception, expression of somatic and negative affective components of morphine withdrawal, and acquisition of morphine-induced conditioned place preference in rats. I.c.v administration of DL-TBOA (10 nmol) to naive rats did not affect the acute antinociceptive effect of morphine. I.c.v. administration of DL-TBOA (10 nmol) to morphine-dependent rats significantly facilitated the expression of naloxone-precipitated somatic signs and conditioned place aversion. DL-TBOA (3 and 10 nmol) significantly facilitated acquisition of morphine-induced conditioned place preference. DL-TBOA itself produced neither conditioned place aversion nor place preference in naive rats. These results suggest that central glutamate transporters play inhibitory roles in the expression of somatic and negative affective components of morphine withdrawal and the reinforcing effect of morphine.
Asunto(s)
Sistema de Transporte de Aminoácidos X-AG/antagonistas & inhibidores , Ácido Aspártico/farmacología , Condicionamiento Operante/efectos de los fármacos , Morfina/farmacología , Síndrome de Abstinencia a Sustancias/fisiopatología , Sistema de Transporte de Aminoácidos X-AG/fisiología , Animales , Condicionamiento Operante/fisiología , Masculino , Ratas , Ratas Sprague-Dawley , Síndrome de Abstinencia a Sustancias/psicologíaRESUMEN
Several lines of evidence have suggested that the glutamatergic system in the nucleus accumbens (NAc) plays an important role in the conditioned rewarding effect of drugs of abuse. In addition, it is recognized that extracellular glutamate is rapidly removed from the synaptic cleft by Na+-dependent glutamate transporters in neurons and glial cells, thereby maintaining physiological levels of glutamate. We previously reported that activation of glutamate uptake by a glutamate transporter activator attenuated the acquisition of conditioned place preference induced by methamphetamine and morphine in mice. In the present study, we examined the effects of gene transfer of a glial glutamate transporter, GLT-1, into the NAc shell by recombinant adenoviruses on methamphetamine- and morphine-induced conditioned place preference in rats. Bilateral infusion of the recombinant adenoviruses into the NAc shell efficiently increased GLT-1 expression surrounding the infusion site, at least during the period 2-8 days after the infusion. In the conditioned place preference paradigm, animals were conditioned with repeated subcutaneous injections of methamphetamine (2 mg/kg) or morphine (3 mg/kg). Intra-NAc shell overexpression of GLT-1 before the conditioning significantly attenuated the conditioned place preference induced by methamphetamine or morphine, when compared with control. However, it had no effect on the somatic signs of naloxone-precipitated morphine withdrawal. These results suggest that GLT-1 within the NAc shell plays an inhibitory role in the conditioned rewarding effects of methamphetamine and morphine but not the physical dependence on morphine.
Asunto(s)
Estimulantes del Sistema Nervioso Central/farmacología , Condicionamiento Operante/efectos de los fármacos , Transportador 2 de Aminoácidos Excitadores/genética , Metanfetamina/farmacología , Morfina/farmacología , Narcóticos/farmacología , Núcleo Accumbens/fisiología , Adenoviridae/genética , Animales , Western Blotting , Técnicas de Transferencia de Gen , Masculino , Dependencia de Morfina/genética , Naloxona/farmacología , Antagonistas de Narcóticos/farmacología , Núcleo Accumbens/metabolismo , Ratas , Ratas Sprague-DawleyRESUMEN
Glomerulonephritis (GN) is a progressive inflammation that may be caused by a variety of underlying disorders. It is the primary cause of chronic renal failure and end-stage renal disease, which require dialysis and transplantation worldwide. Immunosuppressive therapy has been used to treat GN clinically, but this treatment has had insufficient therapeutic effects. Here, we show that protein kinase CK2 is a key molecule in the progression of GN. cDNA microarray analysis identified CK2alpha, the catalytic subunit of CK2, as a GN-related, differentially expressed gene. Overexpression of CK2alpha was noted in the proliferative glomerular lesions in rat GN models and in renal biopsy specimens from lupus nephritis or IgA nephropathy patients. Administration of either antisense oligodeoxynucleotide against CK2alpha or low molecular weight CK2-specific inhibitors effectively prevented the progression of renal pathology in the rat GN models. The resolution of GN by CK2 inhibition may result from its suppression of extracellular signal-regulated kinase-mediated cell proliferation, and its suppression of inflammatory and fibrotic processes that are enhanced in GN. Our results show that CK2 plays a critical role in the progression of immunogenic renal injury, and therefore, CK2 is a potential target for GN therapy.
Asunto(s)
Quinasa de la Caseína II/antagonistas & inhibidores , Glomerulonefritis/tratamiento farmacológico , Oligodesoxirribonucleótidos Antisentido/farmacología , Subunidades de Proteína/antagonistas & inhibidores , Análisis de Varianza , Animales , Apigenina/administración & dosificación , Apigenina/farmacología , Apigenina/uso terapéutico , Nitrógeno de la Urea Sanguínea , Western Blotting , Quinasa de la Caseína II/metabolismo , Creatinina/sangre , Emodina/administración & dosificación , Emodina/farmacología , Emodina/uso terapéutico , Sueros Inmunes/administración & dosificación , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Riñón/patología , Masculino , Oligodesoxirribonucleótidos Antisentido/administración & dosificación , Oligodesoxirribonucleótidos Antisentido/uso terapéutico , Análisis de Secuencia por Matrices de Oligonucleótidos , Prednisolona , Subunidades de Proteína/metabolismo , Ratas , Ratas Wistar , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Organismos Libres de Patógenos EspecíficosRESUMEN
There is a body of evidence implying the involvement of the central glutamatergic system in morphine dependence. We previously reported changes in the mRNA expression of a glial glutamate transporter GLT-1 in some brain regions of morphine-dependent and naloxone-precipitated withdrawal rats, and inhibition of morphine physical dependence by a glutamate transporter activator in mice. These findings support the possibility that glutamate transporters such as GLT-1 are involved in morphine dependence. In this study, we examined the effects of gene transfer of GLT-1 into the locus coeruleus (LC) by recombinant adenoviruses on morphine physical dependence in rats. We constructed recombinant adenoviruses that successfully delivered the GLT-1 gene in vitro and in vivo. Local overexpression of GLT-1 within the bilateral LC by the recombinant adenoviruses before implantation of the morphine pellet significantly inhibited various somatic signs of naloxone-precipitated morphine withdrawal, compared with the control. These results suggest that GLT-1 within the LC plays an inhibitory role in morphine physical dependence.