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1.
BMC Neurol ; 16: 77, 2016 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-27215274

RESUMO

BACKGROUND: Andrographis paniculata (A. paniculata), a medicinal plant, has shown anti-inflammatory, neuroprotective and antifibrotic effects in animal models as well as clinical efficacy in different studies, including an anti-fatigue effect in autoimmune diseases such as rheumatoid arthritis. In multiple sclerosis (MS), fatigue is rated as one of the most common and disabling symptoms. In the present trial, we investigated the effect of A. paniculata on relapse rate and fatigue in relapsing-remitting MS (RRMS) patients receiving interferon beta. METHODS: A randomised double-blind placebo-controlled trial assessed the effects of 170 mg of A. paniculata dried extract tablet b.i.d. p.o. on relapse rate and fatigue using the Fatigue Severity Scores (FSS) over 12 months in RRMS patients receiving interferon. The Expanded Disability Status Scale (EDSS) score, inflammatory parameters and radiological findings were also investigated. Twenty-five patients were enrolled, and twenty-two patients were ultimately analysed and randomised to the active or placebo group. RESULTS: Patients treated with A. paniculata showed a significant reduction in their FSS score as compared to the placebo, equivalent to a 44 % reduction at 12 months. No statistically significant differences were observed for relapse rate, EDSS or inflammatory parameters, with a trend in reducing new lesions among the A. paniculata group. One patient in the A. paniculata group presented with a mild and transient skin rash, which was alleviated with anti-histamine treatment for three weeks. CONCLUSION: A. paniculata was well tolerated in patients and no changes in clinical parameters were observed. A. paniculata significantly reduces fatigue in patients with RRMS receiving interferon beta in comparison to placebo and only interferon beta treatment. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02280876 ; Trial registration date: 20.10.2014.


Assuntos
Andrographis , Fadiga/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/complicações , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Adolescente , Adulto , Animais , Método Duplo-Cego , Fadiga/etiologia , Feminino , Humanos , Interferon beta/uso terapêutico , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Adulto Jovem
2.
Transl Psychiatry ; 1: e20, 2011 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-22832522

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by a progressive deterioration of cognitive abilities, amyloid-ß peptide (Aß) accumulation and synaptic alterations. Previous studies indicated that hyperforin, a component of the St John's Wort, prevents Aß neurotoxicity and some behavioral impairments in a rat model of AD. In this study we examined the ability of tetrahydrohyperforin (IDN5607), a stable hyperforin derivative, to prevent the cognitive deficit and synaptic impairment in an in vivo model of AD. In double transgenic APPswe/PSEN1ΔE9 mice, IDN5706 improves memory and prevents the impairment of synaptic plasticity in a dose-dependent manner, inducing a recovery of long-term potentiation. In agreement with these findings, IDN5706 prevented the decrease in synaptic proteins in hippocampus and cortex. In addition, decreased levels of tau hyperphosphorylation, astrogliosis, and total fibrillar and oligomeric forms of Aß were determined in double transgenic mice treated with IDN5706. In cultured cells, IDN5706 decreased the proteolytic processing of the amyloid precursor protein that leads to Aß peptide generation. These findings indicate that IDN5706 ameliorates AD neuropathology and could be considered of therapeutic relevance in AD treatment.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Floroglucinol/análogos & derivados , Presenilina-1/genética , Processamento de Proteína Pós-Traducional , Transmissão Sináptica/genética , Terpenos/farmacologia , Proteínas tau/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/prevenção & controle , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/genética , Precursor de Proteína beta-Amiloide/antagonistas & inibidores , Precursor de Proteína beta-Amiloide/genética , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Floroglucinol/administração & dosagem , Floroglucinol/farmacologia , Processamento de Proteína Pós-Traducional/genética , Transmissão Sináptica/efeitos dos fármacos , Terpenos/administração & dosagem
3.
Curr Alzheimer Res ; 7(2): 126-33, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19939230

RESUMO

The use of natural compounds is an interesting stratagem in the search of drugs with therapeutic potential for the treatment of Alzheimer's disease (AD). We report here the effect of the hyperforin derivative (IDN5706, tetrahydrohyperforin), a semi-synthetic derivative of the St. John's Wort, on the brain neuropathology, learning and memory in a double transgenic (APPswe, PS-1dE9) mouse model of AD. Results indicate that, IDN5706 alleviates memory decline induced by amyloid-beta (Abeta) deposits as indicated by the Morris water maze paradigm. Moreover, the analysis of Abeta deposits by immunodetection and thioflavin-S staining of brain sections, only reveals a decrease in the frequency of the larger-size Abeta deposits, suggesting that IDN5706 affected the turnover of amyloid plaques. Immunohistochemical analysis, using GFAP and n-Tyrosine indicated that the hyperforin derivative prevents the inflammatory astrocytic reaction and the oxidative damage triggered by high Abeta deposit levels. We conclude that the hyperforin derivative, IDN5706, has therapeutic potential for prevention and treatment of AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Transtornos da Memória/tratamento farmacológico , Floroglucinol/análogos & derivados , Terpenos/farmacologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/efeitos dos fármacos , Peptídeos beta-Amiloides/metabolismo , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/patologia , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Compostos Bicíclicos com Pontes/farmacologia , Compostos Bicíclicos com Pontes/uso terapêutico , Modelos Animais de Doenças , Encefalite/tratamento farmacológico , Encefalite/fisiopatologia , Encefalite/prevenção & controle , Proteína Glial Fibrilar Ácida/análise , Proteína Glial Fibrilar Ácida/metabolismo , Gliose/tratamento farmacológico , Gliose/fisiopatologia , Gliose/prevenção & controle , Humanos , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Transtornos da Memória/metabolismo , Transtornos da Memória/fisiopatologia , Camundongos , Camundongos Transgênicos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Floroglucinol/farmacologia , Floroglucinol/uso terapêutico , Terpenos/uso terapêutico , Tirosina/análise , Tirosina/metabolismo
4.
Clin Rheumatol ; 28(8): 931-46, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19408036

RESUMO

Andrographis paniculata (Burm. f.) Wall ex Nees (Acanthaceae) possesses anti-inflammatory effects, attributed to the main constituent andrographolide proposed as alternative in the treatment of autoimmune disease. A prospective, randomized, double blind, and placebo-controlled study in patients with rheumatoid arthritis (RA) was performed. Tablets (Paractin) made of an extract of A. paniculata (30% total andrographolides) were administered three times a day for 14 weeks, after a 2-week washout period to 60 patients with active RA. The primary outcomes were pain intensity measured using a horizontal visual analog pain scale (VAPS). In addition, ACR, EULAR, and SF36 clinical parameters were recorded. The intensity of joint pain decreased in the active vs placebo group at the end of treatment, although these differences were not statistically significant. A significant diminishing for week in tender joint -0.13 95% confidence interval (CI; -0.22 to 0.06; p = 0.001), number of swollen joints -0.15 95%CI (-0.29 to -0.02; p = 0.02), total grade of swollen joint -0.27 95%CI (-0.48 to -0.07; p = 0.010), number of tender joints -0.25 95%CI (-0.48 to -0.02; p = 0.033), total grade of swollen joints -0.27 95%CI (-0.48 to -0.07; p = 0.01), total grade of tender joints -0.47 95%CI (-0.77 to -0.17; p = 0.002) and HAQ -0.52 95%CI (-0.82 to -0.21; p < 0.001) and SF36 0.02 95%CI (0.01 to 0.02; p < 0.001) health questionnaires was observed within the group with the active drug. Moreover, it was associated to a reduction of rheumatoid factor, IgA, and C4. These findings suggest that A. paniculata could be a useful "natural complement" in the treatment of AR; however, a larger trial and a more extended period of treatment is necessary in order to corroborate these results.


Assuntos
Andrographis , Artralgia/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Adolescente , Adulto , Idoso , Arsenicais , Artrite Reumatoide/sangue , Artrite Reumatoide/diagnóstico por imagem , Cloroquina/uso terapêutico , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Glutationa/análogos & derivados , Humanos , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Placebos , Folhas de Planta , Prednisona/uso terapêutico , Estudos Prospectivos , Radiografia , Índice de Gravidade de Doença , Adulto Jovem
5.
Mini Rev Med Chem ; 9(2): 153-68, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19200021

RESUMO

The importance of neutrophils in human disease such as rheumatoid arthritis, asthma, adult respiratory distress syndrome, and COPD has prompted the search for drugs capable to slow down neutrophil-dependent inflammation, without interference with innate immune responses. In this review, we summarize new potential drugs targets against neutrophils mediated inflammatory responses.


Assuntos
Anti-Inflamatórios/farmacologia , Inflamação/tratamento farmacológico , Inflamação/patologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/patologia , Animais , Humanos , Imunidade Inata/efeitos dos fármacos
6.
Vet Immunol Immunopathol ; 115(3-4): 286-98, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17157922

RESUMO

Propionate is a short-chain fatty acid produced under normal physiological conditions in the rumen of cattle. It is also involved in the inflammatory process and neutrophil function via calcium release, reactive oxygen species and intracellular pH (pH(i)) changes. This study examined the effect of propionate on the pH(i) of bovine neutrophils; specifically if pH(i) changes are controlled by calcium flux, and the mitogen-activated protein kinase (MAPK) pathway. Propionate caused rapid intracellular acidification and sustained alkalinization in bovine neutrophils loaded with 2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein acetoxymethyl ester (BCECF-AM), a fluorescent indicator of pH(i). The acidification phase seems to be controlled by intracellular calcium release and p38 MAPK pathway. The pH recovery phenomenon was mediated by an amiloride-sensitive Na+/H+ exchanger and H+ channel, and was inhibited by UO126 (an ERK1/2 MAPK phosphorylation inhibitor), Gö6850 (a PKC inhibitor) and calcium chelating. Ionomycin, a calcium ionophore, induced intracellular acidification and sustained alkalinization. The intracellular acidification was strongly inhibited by BAPTA-AM (an intracellular calcium chelator) and SB203580 (a p38 MAPK inhibitor). In addition, the intracellular alkalinization was reduced by EGTA (a calcium chelator), UO126, LY294002 (a PI3K inhibitor) and Gö6850. Propionate did not increase superoxide production, however it reduced the superoxide production induced by platelet-activating factor (PAF), and increased the release of superoxide induced by ionomycin. Our results suggest that propionate-induced intracellular acidification is mediated by intracellular calcium release and p38 MAPK activation, and that pH recovery is controlled via ERK1/2 MAPK, PKC and calcium entry in bovine neutrophils.


Assuntos
Cálcio/sangue , Bovinos/sangue , MAP Quinases Reguladas por Sinal Extracelular/sangue , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Propionatos/farmacologia , Proteína Quinase C/sangue , Animais , Butadienos/farmacologia , Quelantes/farmacologia , Cromonas/farmacologia , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Feminino , Concentração de Íons de Hidrogênio , Imidazóis/farmacologia , Indóis/farmacologia , Ionomicina/farmacologia , Maleimidas/farmacologia , Morfolinas/farmacologia , Neutrófilos/enzimologia , Nitrilas/farmacologia , Proteína Quinase C/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Trocadores de Sódio-Hidrogênio/metabolismo , Espectrometria de Fluorescência/veterinária , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/sangue
7.
Mol Psychiatry ; 11(11): 1032-48, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16880827

RESUMO

The major protein constituent of amyloid deposits in Alzheimer's disease (AD) is the amyloid beta-peptide (Abeta). In the present work, we have determined the effect of hyperforin an acylphloroglucinol compound isolated from Hypericum perforatum (St John's Wort), on Abeta-induced spatial memory impairments and on Abeta neurotoxicity. We report here that hyperforin: (1) decreases amyloid deposit formation in rats injected with amyloid fibrils in the hippocampus; (2) decreases the neuropathological changes and behavioral impairments in a rat model of amyloidosis; (3) prevents Abeta-induced neurotoxicity in hippocampal neurons both from amyloid fibrils and Abeta oligomers, avoiding the increase in reactive oxidative species associated with amyloid toxicity. Both effects could be explained by the capacity of hyperforin to disaggregate amyloid deposits in a dose and time-dependent manner and to decrease Abeta aggregation and amyloid formation. Altogether these evidences suggest that hyperforin may be useful to decrease amyloid burden and toxicity in AD patients, and may be a putative therapeutic agent to fight the disease.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/efeitos dos fármacos , Hypericum , Floroglucinol/análogos & derivados , Extratos Vegetais/farmacologia , Terpenos/farmacologia , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Amiloidose/tratamento farmacológico , Amiloidose/metabolismo , Análise de Variância , Animais , Compostos Bicíclicos com Pontes/farmacologia , Compostos Bicíclicos com Pontes/uso terapêutico , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Esquema de Medicação , Reação de Fuga/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Microinjeções , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/uso terapêutico , Floroglucinol/farmacologia , Floroglucinol/uso terapêutico , Fitoterapia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Terpenos/uso terapêutico , Fatores de Tempo
8.
Phytother Res ; 15(3): 235-9, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11351359

RESUMO

The possible relaxation of uterine smooth muscle by Andrographis paniculata dried extract via a blockade of voltage operated calcium channels was investigated in rats. Uterine horns pretreated with oestradiol were incubated in Ca(+2) -free Jalon's solution and stimulated with KCl (20-60 mM) in order to produce depolarization of the membrane. The isometric contractile response to 1 mM or cumulative concentrations of CaCl2 were blockaded by 0.2, 0.4 and 0.8 mg/mL of A. paniculata. The maximum contractile response induced by acetylcholine was moderately antagonized by A. paniculata. The possible blockade of Ca(+2) entry by A. paniculata was evaluated with (45)Ca(+2) uptake in uterine rings incubated with free-Ca(+2)-Ringer's solution high in K+ (KCl 40 mM). The influx was completely blockaded with 0.4 mg/mL of A. paniculata. These results strongly suggest that A. paniculata blockades voltage operated calcium channels inhibiting the entry of Ca(+2) from the external medium.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Relaxamento Muscular/efeitos dos fármacos , Plantas Medicinais , Contração Uterina/efeitos dos fármacos , Animais , Feminino , Ratos , Ratos Sprague-Dawley
9.
J Ethnopharmacol ; 71(1-2): 115-21, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10904154

RESUMO

The possible blockade of voltage-operated calcium channels (VOCs) by Andrographis paniculata dried extract in vas deferens smooth muscle was investigated in rats. The tissues were incubated in Ca(2+)-free Kreb's solution and stimulated with KCl (40 mM) to produce depolarisation of the membrane. The isometric contractile response to cumulative concentrations of CaCl(2) was effectively blockaded by 0.2 and 0.4 mg/ml A. paniculata. In other experiments, the maximum contractile response induced by norepinephrine was not antagonised by 0.2, 0.4 or 0.8 mg/ml A. paniculata. The possible blockade of Ca(2+) entry by A. paniculata was evaluated with 45Ca(2+) uptake in vas deferens treated with reserpine (5 and 2.5 mg/kg) 48 and 24 h before the experiments. Epididymal segments were incubated with Ca(2+)-free Kreb's solution with KCl, 25 and 50 mM. The influx was completely blockaded with 0.4 mg/ml A. paniculata. These results suggest that A. paniculata selectively blockades VOCs, hence inhibiting the 45Ca(2+) influx.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo P/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Plantas Medicinais/química , Ducto Deferente/efeitos dos fármacos , Animais , Ásia , Bloqueadores dos Canais de Cálcio/isolamento & purificação , Cloreto de Cálcio/farmacologia , Radioisótopos de Cálcio , Chile , Técnicas In Vitro , Masculino , Norepinefrina/farmacologia , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley , Vasoconstritores/farmacologia
10.
Phytomedicine ; 6(4): 217-23, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10589439

RESUMO

The objective of our study was to measure the effectiveness of Andrographis paniculata SHA-10 extract in reducing the prevalence and intensity of symptoms and signs of common cold as compared with a placebo. A group of 158 adult patients of both sexes completed the randomized double blind study in Valdivia, Chile. The patients were divided in two equal size groups, one of which received Andrographis paniculata dried extract (1200 mg/day) and the other a placebo during a period of 5 days. Evaluations for efficacy were performed by the patient at day 0, 2, and 4 of the treatment; each completed a self-evaluation (VAS) sheet with the following parameters: headache, tiredness, earache, sleeplessness, sore throat, nasal secretion, phlegm, frequency and intensity of cough. In order to quantify the magnitude of the reduction in the prevalence and intensity of the signs and symptoms of common cold, the risk (Odds Ratio = OR) was calculated using a logistic regression model. At day 2 of treatment a significant decrease in the intensity of the symptoms of tiredness (OR = 1.28; 95% CI 1.07-1.53), sleeplessness (OR = 1.71; 95% CI 1.38-2.11), sore throat (OR = 2.3; 95% CI 1.69-3.14) and nasal secretion (OR = 2.51; 95% CI 1.82-3.46) was observed in the Andrographis SHA-10 group as compared with the placebo group. At day 4, a significant decrease in the intensity of all symptoms was observed for the Andrographis paniculata group. The higher OR values were for the following parameters: sore throat (OR = 3.59; 95% CI 2.04-5.35), nasal secretion (OR = 3.27; 95% CI 2.31-4.62) and earache (OR = 3.11; 95% CI 2.01-4.80) for Andrographis paniculata treatment over placebo, respectively. It is concluded that Andrographis paniculata had a high degree of effectiveness in reducing the prevalence and intensity of the symptoms in uncomplicated common cold beginning at day two of treatment. No adverse effects were observed or reported.


Assuntos
Antivirais/uso terapêutico , Resfriado Comum/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Extratos Vegetais/uso terapêutico , Plantas Medicinais , Adulto , Antivirais/química , Diterpenos/análise , Método Duplo-Cego , Medicamentos de Ervas Chinesas/química , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Medição da Dor/métodos , Extratos Vegetais/química , Resultado do Tratamento
11.
J Ethnopharmacol ; 58(3): 219-24, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9421258

RESUMO

The possible testicular toxicity of Andrographis paniculata, Nees (Acanthaceae) standardized dried extract was evaluated in male Sprague Dawley rats for 60 days. No testicular toxicity was found with the treatment of 20, 200 and 1000 mg/kg during 60 days as evaluated by reproductive organ weight, testicular histology, ultrastructural analysis of Leydig cells and testosterone levels after 60 days of treatment. It is concluded that Andrographis paniculata dried extract did not produce subchronic testicular toxicity effect in male rats.


Assuntos
Plantas Medicinais/química , Doenças Testiculares/induzido quimicamente , Animais , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/ultraestrutura , Masculino , Microscopia Eletrônica , Tamanho do Órgão/efeitos dos fármacos , Extratos Vegetais/toxicidade , Ratos , Ratos Sprague-Dawley , Doenças Testiculares/patologia , Testículo/patologia , Testículo/ultraestrutura , Testosterona/sangue
12.
Phytomedicine ; 4(2): 101-4, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23195395

RESUMO

In a randomized placebo-controlled double blind study, the possible preventive effect against common colds of Kan Jang tablets made from Andrographis paniculata (Barm. F.) (Nees) dried extract was tudied during the winter season. The study was carried in a rural school. The students were divided in two groups, of which Group 1 (n=54), received 2 tablets of Kan Jang per day and Group 2 (n=53), 2 tablets of a placebo (P) per day during three months. The individuals were evaluated weekly by a clinician who diagnosed the presence or absence of common colds during the three months. The analysis of the occurrence of colds revealed that the administration of Kan Jang after the first month did not produced any significant difference. However, after the third month of intake of Kan Jang there was a significant decrease in the incidence of colds as compared to the placebo group. The rate of incidence of colds among the students treated with Kan Jang was 30% (16/54) compared to 62% (33/53). The relative risk of catching a cold was therefore 2.1 (1.32-3.33, 95% confidence interval) times lower for the Kan Jang group. The attributable protective effect of Kan Jang was 33%. The results suggest that Kan Jang tablets have a preventive effect against common colds during the winter period.

14.
Planta Med ; (6): 542-3, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17345497
18.
Neuroendocrinology ; 35(3): 178-85, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6890152

RESUMO

The rat pars tuberalis was studied with conventional electron microscopy and immunocytochemistry for the demonstration of luteinizing hormone (LH). The LH-secreting cells were preferentially located in two regions of the pars tuberalis (PT), namely, that surrounding the neural stalk and that occupying the tuberoinfundibular sulci. Dialyzed extracts of PT prepared after removal of the pituitary stalk, had the capacity to induce ovulation in chlorpromazine-blocked rats in proestrus. In radioimmunoassays carried out under the same conditions, the PT extracts yielded displacement curves parallel to those of standard LH. The immunoreactive LH content of the female PT was determined at three phases of the estrous cycle: diestrus, afternoon of proestrus and estrus. The lowest values were found in rats sacrificed in the evening of proestrus (18.00 h), and they were about one sixth of the peak values found at estrus. 1 month after inducing lesions in the preoptic area of female rats, the LH content of the PT was four times higher than the highest values found during the estrous cycle. The results suggest that the rat PT does secret LH, and that this secretory activity fluctuates with the estrous cycle, but in a manner that differs from that reported for LH secretion of the pars distalis.


Assuntos
Estro , Hormônio Luteinizante/metabolismo , Adeno-Hipófise/metabolismo , Área Pré-Óptica/fisiologia , Animais , Clorpromazina/farmacologia , Estro/efeitos dos fármacos , Feminino , Masculino , Eminência Mediana/metabolismo , Microscopia Eletrônica , Muridae , Ovulação/efeitos dos fármacos , Gravidez , Radioimunoensaio
19.
Exp Brain Res ; 35(1): 127-34, 1979 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-571347

RESUMO

The noradrenergic innervation of the medial preoptic area (MPO) and the hypothalamus is provided by mesencephalic neurons via the ventral noradrenergic tract. Fibers of these neurons emerge through the MPO. Bilateral microinjections of 6-OHDA into the ventral noradrenergic bundle (VNB) depletes large parts of the diencephalon of norepinephrine (NE) and dopamine (DA). Since the total hypothalamic DA content is of intrahypothalamic origin, 6-OHDA injection into the VNB does not reduce hypothalamic DA content. Similarly microinjections of 6-OHDA into the MPO reduces hypothalamic and preoptic NE content without altering NE concentrations in other diencephalic structures. Microinjections of 6-OHDA and of the carrier solution of 6-OHDA into the VNB or into the MPO of female rats with regular estrous cycles results in a slight disturbance of the cyclic activity for few days. Within 1--4 days normal cyclic activity is resumed. Preovulatory LH release is substantially reduced 8--12 days after injection of 6-OHDA into the VNB or into the MPO. On the basis of these and previous results it is concluded that the availability of NE in the MPO is an important factor in determining the hight of the preovulatory LH surge.


Assuntos
Hipotálamo/fisiologia , Hormônio Luteinizante/sangue , Norepinefrina/fisiologia , Ovulação , Área Pré-Óptica/fisiologia , Animais , Dopamina/metabolismo , Feminino , Hidroxidopaminas/farmacologia , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Vias Neurais/fisiologia , Norepinefrina/metabolismo , Ovulação/efeitos dos fármacos , Gravidez , Área Pré-Óptica/efeitos dos fármacos , Área Pré-Óptica/metabolismo , Proestro/efeitos dos fármacos , Ratos
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