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1.
Clin Hypertens ; 29(1): 25, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37653547

RESUMO

Nocturnal blood pressure (BP) has been shown to have a significant predictive value for cardiovascular disease. In some cases, it has a superior predictive value for future cardiovascular outcomes than daytime BP. As efficacy of BP medications wanes during nighttime and early morning, control of nocturnal hypertension and morning hypertension can be difficult. As such, chronotherapy, the dosing of BP medication in the evening, has been an ongoing topic of interest in the field of hypertension. Some studies have shown that chronotherapy is effective in reducing nocturnal BP, improving non dipping and rising patterns to dipping patterns, and improving cardiovascular prognosis. However, criticism and concerns have been raised regarding the design of these studies, such as the Hygia study, and the implausible clinical benefits in cardiovascular outcomes considering the degree of BP lowering from bedtime dosing. Studies have shown that there is no consistent evidence to suggest that routine administration of antihypertensive medications at bedtime can improve nocturnal BP and early morning BP control. However, in some cases of uncontrolled nocturnal hypertension and morning hypertension, such as in those with diabetes mellitus, chronic kidney disease, and obstructive sleep apnea, bedtime dosing has shown efficacy in reducing evening and early morning BP. The recently published the Treatment in Morning versus Evening (TIME) study failed to demonstrate benefit of bedtime dosing in reducing cardiovascular outcomes in patients with hypertension. With issues of the Hygia study and negative results from the TIME study, it is unclear at this time whether routine bedtime dosing is beneficial for reducing cardiovascular outcomes.

2.
BMC Pregnancy Childbirth ; 22(1): 226, 2022 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-35305601

RESUMO

BACKGROUND: Hypertension has been known to increase the risk of obstetric complications. Recently, the American College of Cardiology endorsed lower thresholds for hypertension as systolic blood pressure of 130-139 mmHg or diastolic blood pressure 80-89 mmHg. However, there is a paucity of information regarding the impact of pre-pregnancy blood pressure on pregnancy outcomes. We aimed to evaluate the effect of pre-pregnancy blood pressure on maternal and neonatal complications. METHODS: In this nationwide, population based study, pregnant women without history of hypertension and pre-pregnancy blood pressure < 140/90 mmHg were enrolled. The primary outcome of composite morbidity was defined as any of the followings: preeclampsia, placental abruption, stillbirth, preterm birth, or low birth weight. RESULTS: A total of 375,305 pregnant women were included. After adjusting for covariates, the risk of composite morbidity was greater in those with stage I hypertension in comparison with the normotensive group (systolic blood pressure, odds ratio = 1.68, 95% CI: 1.59 - 1.78; diastolic blood pressure, odds ratio = 1.56, 95% CI: 1.42 - 1.72). There was a linear association between pre-pregnancy blood pressure and the primary outcome, with risk maximizing at newly defined stage I hypertension and with risk decreasing at lower blood pressure ranges. CONCLUSIONS: 'The lower, the better' phenomenon was still valid for both maternal and neonatal outcomes. Our results suggest that the recent changes in diagnostic thresholds for hypertension may also apply to pregnant women. Therefore, women with stage I hypertension prior to pregnancy should be carefully observed for adverse outcomes.


Assuntos
Pressão Sanguínea , Hipertensão/patologia , Complicações Cardiovasculares na Gravidez/patologia , Complicações na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Estudos de Coortes , Bases de Dados Factuais , Feminino , Humanos , Programas Nacionais de Saúde , Gravidez , República da Coreia
3.
Clin Ther ; 43(8): 1419-1430, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34332788

RESUMO

PURPOSE: Residual cardiovascular risk in patients with hypertriglyceridemia, despite optimal low-density lipoprotein cholesterol levels being achieved with intensive statin treatment, is a global health issue. The purpose of this study was to investigate the efficacy and tolerability of treatment with a combination of high-dose atorvastatin/Ω-3 fatty acid compared to atorvastatin + placebo in patients with hypertriglyceridemia who did not respond to statin treatment. METHODS: In this multicenter, randomized, double-blind, placebo-controlled study, patients who had residual hypertriglyceridemia after a 4-week run-in period of atorvastatin treatment were randomly assigned to receive UI-018 (fixed-dose combination atorvastatin/Ω-3 fatty acid 40 mg/4 g) or atorvastatin 40 mg + placebo (control). The primary efficacy end points were the percentage change from baseline in non-high density lipoprotein cholesterol (non-HDL-C) level at the end of treatment and the adverse events recorded during treatment. A secondary end point was the percentage change from baseline in triglyceride level. FINDINGS: After 8 weeks of treatment, the percentage changes from baseline in non-HDL-C (-4.4% vs +0.6%; p = 0.02) and triglycerides (-18.5% vs +0.9%; p < 0.01) were significantly greater in the UI-018 group (n = 101) than in the control group (n = 99). These changes were present in subgroups of advanced age (≥65 years), status (body mass index ≥25 kg/m2), or without diabetes. The prevalences of adverse events did not differ between the 2 treatment groups. IMPLICATIONS: In patients with residual hypertriglyceridemia despite receiving statin treatment, a combination of high-dose atorvastatin/Ω-3 fatty acid was associated with a greater reduction of triglyceride and non-HDL-C compared with atorvastatin + placebo, without significant adverse events.


Assuntos
Ácidos Graxos Ômega-3 , Inibidores de Hidroximetilglutaril-CoA Redutases , Hipertrigliceridemia , Idoso , Atorvastatina/efeitos adversos , Método Duplo-Cego , Humanos , Hipertrigliceridemia/tratamento farmacológico , Pirróis , Resultado do Tratamento , Triglicerídeos
4.
J Am Heart Assoc ; 8(6): e011077, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30845873

RESUMO

Background Many patients with heart failure ( HF ) with reduced ejection fraction ( HF r EF ) experience improvement or recovery of left ventricular ejection fraction ( LVEF ). Data on clinical characteristics, outcomes, and medical therapy in patients with HF with improved ejection fraction (HFiEF) are scarce. Methods and Results Of 5625 consecutive patients hospitalized for acute HF in the KorAHF (Registry [Prospective Cohort] for Heart Failure in Korea) study, 5103 patients had baseline echocardiography and 2302 patients had follow-up echocardiography at 12 months. HF phenotypes were defined as persistent HF r EF ( LVEF ≤40% at baseline and at 1-year follow-up), HF i EF ( LVEF ≤40% at baseline and improved up to 40% at 1-year follow-up), HF with midrange ejection fraction (LVEF between 40% and <50%), and HF with preserved ejection fraction ( LVEF ≥50%). The primary outcome was 4-year all-cause mortality from the time of HF i EF diagnosis. Among 1509 HF r EF patients who had echocardiography 1 year after index hospitalization, 720 (31.3%) were diagnosed as having HF i EF . Younger age, female sex, de novo HF , hypertension, atrial fibrillation, and ß-blocker use were positive predictors and diabetes mellitus and ischemic heart disease were negative predictors of HF i EF . During 4-year follow-up, patients with HF i EF showed lower mortality than those with persistent HF r EF in univariate, multivariate, and propensity-score-matched analyses. ß-Blockers, but not renin-angiotensin system inhibitors or mineralocorticoid receptor antagonists, were associated with a reduced all-cause mortality risk (hazard ratio: 0.59; 95% CI , 0.40-0.87; P=0.007). Benefits for outcome seemed similar among patients receiving low- or high-dose ß-blockers (log-rank, P=0.304). Conclusions HF i EF is a distinct HF phenotype with better clinical outcomes than other phenotypes. The use of ß-blockers may be beneficial for these patients. Clinical Trial Registration URL : https://www.clinicaltrials.gov . Unique identifier: NCT01389843.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Ventrículos do Coração/diagnóstico por imagem , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Sistema de Registros , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Idoso , Causas de Morte/tendências , Ecocardiografia , Feminino , Seguimentos , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/fisiopatologia , Hospitalização/tendências , Humanos , Masculino , Pessoa de Meia-Idade , Pontuação de Propensão , Estudos Prospectivos , República da Coreia/epidemiologia , Taxa de Sobrevida/tendências , Fatores de Tempo , Resultado do Tratamento
5.
Drugs ; 76(10): 1015-22, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27272555

RESUMO

Fimasartan is the ninth, and most recent, angiotensin II receptor antagonist approved as an antihypertensive agent. Fimasartan, a pyrimidin-4(3H)-one derivative of losartan with the imidazole ring replaced, which enables higher potency and longer duration than losartan. Fecal elimination and biliary excretion are the predominant elimination pathways of fimasartan and the urinary excretion was found to be less than 3 % 24 h after administration. Fimasartan is primarily catabolized by cytochrome P450 isoform 3A and no significant drug interaction was observed when used in combination with hydrochlorothiazide, amlodipine, warfarin, or digoxin. Fimasartan at a dosage range of 60-120 mg once daily showed an antihypertensive effect over 24 h. In a large, population-based observational study, fimasartan showed an excellent safety profile. Anti-inflammatory and organ-protecting effects of fimasartan have been shown in various preclinical studies, including aortic balloon injury, myocardial infarct ischemia/reperfusion, doxorubicin cardiotoxicity, and ischemic stroke models.


Assuntos
Bloqueadores do Receptor Tipo 2 de Angiotensina II/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Compostos de Bifenilo/uso terapêutico , Hipertensão/tratamento farmacológico , Pirimidinas/uso terapêutico , Tetrazóis/uso terapêutico , Bloqueadores do Receptor Tipo 2 de Angiotensina II/administração & dosagem , Bloqueadores do Receptor Tipo 2 de Angiotensina II/efeitos adversos , Bloqueadores do Receptor Tipo 2 de Angiotensina II/farmacocinética , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/efeitos adversos , Anti-Hipertensivos/farmacocinética , Compostos de Bifenilo/administração & dosagem , Compostos de Bifenilo/efeitos adversos , Compostos de Bifenilo/farmacocinética , Ensaios Clínicos como Assunto , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Quimioterapia Combinada , Humanos , Hipertensão/metabolismo , Estrutura Molecular , Estudos Observacionais como Assunto , Pirimidinas/administração & dosagem , Pirimidinas/efeitos adversos , Pirimidinas/farmacocinética , Tetrazóis/administração & dosagem , Tetrazóis/efeitos adversos , Tetrazóis/farmacocinética , Resultado do Tratamento
6.
Clin Ther ; 38(4): 832-42, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26996246

RESUMO

PURPOSE: Doubling the dose of antihypertensive drugs is necessary to manage hypertension in patients whose disease is uncontrolled. However, this strategy can result in safety issues. This study compared the safety and efficacy of up-titration of the nifedipine gastrointestinal therapeutic system (GITS) with up-titration of valsartan monotherapy; these were also compared with low-dose combinations of the two therapies. METHODS: This prospective, open-label, randomized, active-controlled, multicenter study lasted 8 weeks. If patients did not meet the target blood pressure (BP) after 4 weeks of treatment with low-dose monotherapy, they were randomized to up-titration of the nifedipine GITS dose from 30 mg (N30) to 60 mg or valsartan from 80 mg to 160 mg or they were randomized to receive a low-dose combination of N30 and valsartan 80 mg for another 4 weeks. BP variability was assessed by using the SD or the %CV of the short-term BP measured at clinic. FINDINGS: Of the 391 patients (20~70 years with stage II or higher hypertension) screened for study inclusion, 362 patients who had 3 BP measurements were enrolled. The reduction in the mean systolic/diastolic BP from baseline to week 4 was similar in both low-dose monotherapy groups with either N30 or valsartan 80 mg. BP variability (SD) was unchanged with either therapy, but the %CV was slightly increased in the N30 group. There was no significant difference in BP variability either in SD or %CV between responders and nonresponders to each monotherapy despite the significant difference in the mean BP changes. The up-titration effect of nifedipine GTS from 30 to 60 mg exhibited an additional BP reduction, but this effect was not shown in the up-titration of valsartan from 80 to 160 mg. Although the difference in BP was obvious between high-dose nifedipine GTS and valsartan, the BP variability was unchanged between the 2 drugs and was similar to the low-dose combinations. There was a low rate of adverse events in all treatment groups. In addition, escalating the dose of either nifedipine GITS or valsartan revealed a similar occurrence of adverse effects with low-dose monotherapy or the low-dose combination. IMPLICATIONS: Compared with up-titration of the angiotensin receptor blocker valsartan, up-titration of the calcium channel blocker nifedipine GITS provided no additional increased safety concerns and revealed better mean reductions in BP without affecting short-term BP variability. ClinicalTrials.gov identifier: NCT01071122.


Assuntos
Anti-Hipertensivos , Hipertensão/tratamento farmacológico , Nifedipino , Valsartana , Adulto , Idoso , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/efeitos adversos , Anti-Hipertensivos/uso terapêutico , Humanos , Pessoa de Meia-Idade , Nifedipino/administração & dosagem , Nifedipino/efeitos adversos , Nifedipino/uso terapêutico , Estudos Prospectivos , Valsartana/administração & dosagem , Valsartana/efeitos adversos , Valsartana/uso terapêutico , Adulto Jovem
7.
Neuromolecular Med ; 17(1): 35-46, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25429759

RESUMO

Epilepsy is a common neurological disorder that leads to neuronal excitability and provoke various forms of cellular reorganization in the brain. In this study, we investigate the anti-convulsant and neuroprotective effects of thymoquinone (TQ) and vitamin C against pentylenetetrazole (PTZ)-induced generalized seizures. Epileptic seizures were induced in adult rats using systemic intraperitoneal injections of PTZ (50 mg/kg) for 7 days. Animals pretreated with either TQ or vitamin C or in combination attenuated PTZ-induced seizures and mortality in rats as well neurodegeneration in the cells. Compared to PTZ, TQ and vitamin C significantly prolonged the onset of seizures (p > 0.05) as well decrease the high-grade seizures. Analysis of electroencephalogram (EEG) recordings revealed that TQ or vitamin C supplementation significantly reduced polyspike and epileptiform discharges. Epileptic seizures caused a decline in expression of gamma-aminobutyric acid B1 receptor (GABAB1R) (p > 0.05), unchanged expression of protein kinase A (PKA), decreased calcium/calmodulin-dependent protein kinase II (CaMKII) (p > 0.05) and inhibit the phosphorylation of cAMP response element-binding protein (CREB) (p > 0.05) in cortex and hippocampus, respectively, compared with control. Changes in expression of GABAB1R, CaMKII and CREB by PTZ were reversed by TQ and vitamin C supplementation. Moreover, PTZ significantly increased Bax, decreased Bcl-2 expression and finally the activation of caspase-3. TQ and vitamin C pretreatment reversed all these deleterious effects induced by PTZ. TQ and vitamin C showed anticonvulsant effects via activation of GABAB1R/CaMKII/CREB pathway and suggest a potential therapeutic role in epilepsy.


Assuntos
Anticonvulsivantes/uso terapêutico , Ácido Ascórbico/uso terapêutico , Benzoquinonas/uso terapêutico , Córtex Cerebral/efeitos dos fármacos , Agonistas dos Receptores de GABA-B/uso terapêutico , Hipocampo/efeitos dos fármacos , Proteínas do Tecido Nervoso/fisiologia , Fármacos Neuroprotetores/uso terapêutico , Receptores de GABA-B/fisiologia , Convulsões/tratamento farmacológico , Animais , Anticonvulsivantes/farmacologia , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Ácido Ascórbico/farmacologia , Benzoquinonas/farmacologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Caspase 3/metabolismo , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Convulsivantes/toxicidade , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Eletroencefalografia/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Indução Enzimática/efeitos dos fármacos , Antagonistas de Receptores de GABA-A/toxicidade , Agonistas dos Receptores de GABA-B/farmacologia , Hipocampo/metabolismo , Hipocampo/patologia , Degeneração Neural , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Fármacos Neuroprotetores/farmacologia , Pentilenotetrazol/toxicidade , Ratos , Ratos Sprague-Dawley , Receptores de GABA-B/biossíntese , Receptores de GABA-B/genética , Convulsões/induzido quimicamente , Convulsões/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
8.
Neuropeptides ; 47(5): 347-53, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23830691

RESUMO

Anthocyanins in a variety of plant species have been identified and are known for its hypolipidemic and anti-obesity effects. The effect of anthocyanins extracted from black soybean on body weight and daily food intake in adult rats raised on normal diet were studied. Male Sprague-Dawley rats were daily intra-gastric administered water or anthocyanins 6 mg/kg and 24 mg/kg for 40 days. During this period daily food intake and body weight were measured prior to anthocyanins treatment. These findings showed that anthocyanins treatment resulted in significantly lowered body weight and food intake compared with water treated rats. In addition, anthocyanins dose dependently reduced the adipose tissue size compared with control group. Western blot analysis showed that high dose of anthocyanins treatment significantly reduced the expression of neuropeptide Y (NPY) and increased γ-amino butyric acid receptor (GABAB1R) in hypothalamus. Furthermore, these events were followed by a decreased in expression of GABAB1R downstream signaling molecules protein kinase A-α (PKA) and phosphorylated cAMP-response element binding protein (p-CREB) in hypothalamus. These data support the concept that anthocyanins even in normal circumstances have the capability to reduce body weight and food intake through its modulatory effect on NPY and GABAB1R in hypothalamus. These results suggest that anthocyanins from black soybean seed coat might have a novel role in preventing obesity in rats on normal diet.


Assuntos
Antocianinas/farmacologia , Neuropeptídeo Y/metabolismo , Receptores de GABA-B/metabolismo , Aumento de Peso/efeitos dos fármacos , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Antocianinas/administração & dosagem , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Dieta , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
9.
Neurol Sci ; 34(12): 2137-43, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23494720

RESUMO

Exposure to ethanol during developmental stages leads to several types of neurological disorders. Apoptotic neurodegeneration due to ethanol exposure is a main feature in alcoholism. Exposure of developing animals to alcohol induces apoptotic neuronal death and causes fetal alcohol syndrome. In the present study, we observed the possible protective effect of pyruvate against ethanol-induced neurodegeneration. Exposure of developing mice to ethanol (2.5 g/kg) induces apoptotic neurodegeneration and widespread neuronal cell death in the cortex and thalamus. Co-treatment of pyruvate (500 mg/kg) protects neuronal cell against ethanol by the reduced expression of caspase-3 in these brain regions. Immunohistochemical analysis and TUNNEL at 24 h showed that apoptotic cell death induced by ethanol in the cortex and thalamus is reduced by pyruvate. Histomorphological analysis at 24 h with cresyl violet staining also proved that pyruvate reduced the number of neuronal cell loss in the cortex and thalamus. The results showed that ethanol increased the expression of caspase-3 and thus induced apoptotic neurodegeneration in the developing mice cortex and thalamus, while co-treatment of pyruvate inhibits the induction of caspase-3 and reduced the cell death in these brain regions. These findings, therefore, showed that treatment of pyruvate inhibits ethanol-induced neuronal cell loss in the postnatal seven (P7) developing mice brain and may appear as a safe neuroprotectant for treating neurodegenerative disorders in newborns and infants.


Assuntos
Apoptose/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Etanol/toxicidade , Fármacos Neuroprotetores/farmacologia , Ácido Pirúvico/farmacologia , Tálamo/efeitos dos fármacos , Animais , Caspase 3/metabolismo , Córtex Cerebral/crescimento & desenvolvimento , Córtex Cerebral/patologia , Camundongos , Camundongos Endogâmicos C57BL , Tálamo/crescimento & desenvolvimento , Tálamo/patologia
10.
Eur J Clin Nutr ; 65(1): 110-6, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20877395

RESUMO

BACKGROUND: This study was designed to evaluate the effects of omega-3 fatty acids supplements and simvastatin on lipoproteins and heart rate variability (HRV), a surrogate parameter of cardiac autonomic function, in patients with mixed dyslipidemia. METHODS: This study was a prospective, randomized, open-label study. Among the 171 patients screened, 62 who met the inclusion criteria after 6 weeks on a strict diet therapy were randomized into two treatment groups. The inclusion criteria were mixed dyslipidemia with a high triglyceride level (200-499 mg per 100 ml) and a total cholesterol level >200 mg per 100 ml. After a run-in period of 6 weeks, the patients were randomized into two groups and given a combination treatment with 4 g of omega-3 fatty acids (four 1 g Omacor (eicosapentaenoic acid, 465 mg; docosahexaenoic acid, 375 mg; other omega-3 fatty acids, 60 mg; others 100 mg, Gun-il Pharmacy, Seoul, Korea)) and 20 mg of simvastatin daily or a monotherapy of 20 mg simvastatin for 6 weeks. In the combination therapy group, seven patients dropped out, and in the simvastatin alone therapy group, five patients dropped out during the study period. RESULTS: After 6 weeks of drug treatment, triglyceride levels decreased by 41.0% in the combination treatment group and 13.9% in the simvastatin monotherapy group (from 309.2 ± 95 mg per 100 ml to 177.7 ± 66 versus 294.6 ± 78 mg per 100 ml to 238.3 ± 84 mg per 100 ml, respectively, P = 0.0007). No significant changes in the HRV parameters were observed in either group. CONCLUSION: The combination of omega-3 fatty acids plus simvastatin, which achieved a significantly greater reduction of triglycerides without adverse reactions, should be considered as an optimal treatment option for patients with mixed dyslipidemia.


Assuntos
Dislipidemias/tratamento farmacológico , Ácidos Graxos Ômega-3/administração & dosagem , Frequência Cardíaca/efeitos dos fármacos , Hipolipemiantes/administração & dosagem , Sinvastatina/administração & dosagem , Adulto , Idoso , Povo Asiático , Colesterol/sangue , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/administração & dosagem , Combinação de Medicamentos , Quimioterapia Combinada , Ácido Eicosapentaenoico/administração & dosagem , Feminino , Humanos , Lipoproteínas/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , República da Coreia , Triglicerídeos/sangue
11.
Neurosci Lett ; 471(1): 25-9, 2010 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-20060435

RESUMO

Chronic exposure to ethanol suppresses the male reproductive activity which is primarily involved in the release of hypothalamic gonadotropin-releasing hormone (GnRH). The testicular GnRH and GnRH receptors (GnRH-R) are found in seminiferous tubules, which are predicted to act as a local regulator of spermatogenesis, although the function is not well known. In this study, we investigated the chronic ethanol effect on GnRH mRNA expression in hypothalamus and testis using in situ hybridization and RNase protection assay (RPA). The effect of ethanol on expressional changes of GnRH and GnRH-R mRNA was observed in adult and pubertal rats according to age and time from 2 weeks (short term) and 4 weeks (long term) periods. The results showed that GnRH mRNA expression in adult and pubertal rats was dramatically decreased in the testis while no significant change was observed in hypothalamus after both short and long term exposure to ethanol. The pubertal rats showed decrease in testicular GnRH and GnRH-R mRNA expression, whereas GnRH mRNA was increased significantly, while GnRH-R mRNA was further decreased after long term exposure in adults. This study suggested that chronic ethanol administration is more effective to testicular GnRH and GnRH-R mRNA expression than hypothalamus and causes a negative effect on the spermatogenesis process. Furthermore, our finding suggests that the deteriorative effects of ethanol on gonadal activity are more lethal in puberty than adults.


Assuntos
Etanol/farmacologia , Hormônio Liberador de Gonadotropina/biossíntese , Hipotálamo/efeitos dos fármacos , RNA Mensageiro/biossíntese , Receptores LHRH/biossíntese , Testículo/efeitos dos fármacos , Envelhecimento/metabolismo , Animais , Hipotálamo/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Maturidade Sexual , Testículo/metabolismo , Fatores de Tempo
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