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1.
J Autism Dev Disord ; 53(3): 1053-1065, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35124780

RESUMO

Fetal androgen exposure may be associated with autism spectrum disorder (ASD). We studied 1777 mother-child pairs in the prospective Odense Child Cohort. Prenatal androgen exposure was assessed by maternal 3rd trimester testosterone concentrations, maternal polycystic ovary syndrome (PCOS), and 3 months offspring anogenital distance. ASD traits were assessed at age 3 years with the ASD-symptom scale of the Child Behavior Checklist for ages 1½-5 years. Maternal testosterone was positively associated with traits of ASD in boys (p < 0.05). Maternal PCOS was associated with increased offspring ASD traits (p = 0.046), but became non-significant after excluding parental psychiatric diagnosis. Offspring anogenital distance was not linked to ASD traits. Higher prevalence of ASD in boys could be linked to higher susceptibility to fetal androgen exposure.


Assuntos
Transtorno do Espectro Autista , Síndrome do Ovário Policístico , Efeitos Tardios da Exposição Pré-Natal , Gravidez , Masculino , Feminino , Humanos , Pré-Escolar , Androgênios , Transtorno do Espectro Autista/epidemiologia , Estudos Prospectivos , Testosterona , Síndrome do Ovário Policístico/complicações
2.
Acta Obstet Gynecol Scand ; 100(11): 2053-2065, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34490610

RESUMO

INTRODUCTION: Previous data suggested a link between maternal polycystic ovary syndrome (PCOS) and offspring attention deficit hyperactivity disorder (ADHD), which could be mediated by higher prenatal androgen exposure. MATERIAL AND METHODS: The study was part of the prospective Odense Child Cohort and included 1776 pregnant women, 165 (9%) with PCOS and 1607 (91%) controls. ADHD symptoms at 3 years of age were defined using the parent-reported questionnaire Child Behavior Checklist/1.5-5 (scores >90th centile of Danish national standard). Maternal blood samples were collected in the third trimester measuring total testosterone by mass spectrometry, sex hormone-binding globulin, and calculated free testosterone. Offspring anogenital distance was measured at 3 months of age. Regression models were performed with presence of ADHD symptoms as the dependent variable and adjusted for maternal age, body mass index, parity, smoking status, educational level, and parental psychiatric diagnoses. RESULTS: ADHD symptoms were present in 105/937 (11%) boys and 72/839 (9%) girls. In boys, maternal PCOS was positively associated with ADHD symptoms (unadjusted odds ratio [OR] 1.91, 95% CI 1.07-3.43, p = 0.03, adjusted OR 2.20, 95% CI 1.20-4.02, p = 0.01), whereas maternal PCOS was not associated with ADHD symptoms in girls. Maternal total testosterone, free testosterone, and offspring anogenital distance were not associated with higher risk of ADHD symptoms in the offspring. CONCLUSIONS: Higher risk of ADHD in boys born of mothers with PCOS were not associated with maternal third-trimester testosterone levels or offspring anogenital distance.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Síndrome do Ovário Policístico/complicações , Adulto , Biomarcadores/sangue , Pré-Escolar , Dinamarca/epidemiologia , Feminino , Desenvolvimento Fetal , Humanos , Masculino , Gravidez , Estudos Prospectivos , Fatores de Risco , Fatores Sexuais , Globulina de Ligação a Hormônio Sexual/metabolismo , Inquéritos e Questionários , Testosterona/sangue
3.
Eur Ann Allergy Clin Immunol ; 52(5): 205-209, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31594291

RESUMO

Summary: Background and Objective. Sensitization and allergy to shrimp among Italian house dust mite allergic patients are not well defined and were investigated in a large multicenter study. Methods. Shrimp sensitization and allergy were assessed in 526 house dust mite (HDM)-allergic patients submitted to the detection of IgE to Der p 10 and 100 atopic control not sensitized to HDM. Results. Shrimp allergy occurred in 9% of patients (vs 0% of 100 atopic controls not sensitized to HDM; p minor 0.001). Shrimp-allergic patients were less frequently hypersensitive to airborne allergens other than HDM than crustacean-tolerant subjects (35% vs 58.8%; p minor 0.005). Only 51% of tropomyosin-sensitized patients had shrimp allergy, and these showed significantly higher Der p 10 IgE levels than shrimp-tolerant ones (mean 22.2 KU/l vs 6.2 KU/l; p minor 0.05). Altogether 53% of shrimp-allergic patients did not react against tropomyosin. Conclusions. Shrimp allergy seems to occur uniquely in association with hypersensitivity to HDM allergens and tropomyosin is the main shrimp allergen but not a major one, at least in Italy. Along with tropomyosin-specific IgE levels, monosensitization to HDM seems to represent a risk factor for the development of shrimp allergy among HDM allergic patients.


Assuntos
Antígenos de Dermatophagoides/imunologia , Proteínas de Artrópodes/imunologia , Hipersensibilidade Alimentar/epidemiologia , Tropomiosina/imunologia , Adolescente , Adulto , Animais , Reações Cruzadas , Feminino , Hipersensibilidade Alimentar/imunologia , Humanos , Imunoglobulina E/metabolismo , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Penaeidae , Prevalência , Pyroglyphidae , Adulto Jovem
4.
J Investig Allergol Clin Immunol ; 29(3): 180-205, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30183660

RESUMO

Hymenoptera venom allergy is an epidemiologically underestimated condition and a major cause of morbidity worldwide. Preventing future allergic reactions in patients who experience a systemic reaction is based on the correct management of the emergency followed by an accurate diagnosis, prescription of adrenaline autoinjectors, and, where indicated, specific venom immunotherapy. Some epidemiological studies highlight our poor knowledge of this disease and the frequent inadequacy of its management. Moreover, they emphasize the importance of such a life-saving treatment as specific immunotherapy. The availability of high-quality hymenoptera venom extracts for diagnostic and therapeutic use has dramatically improved the prognosis and quality of life of allergic patients. Subcutaneous venom immunotherapy is currently the most effective form of allergen-based immunotherapy, with a carry-over effect lasting up to several years after its interruption. This report on the management of hymenoptera venom-allergic children and adults was prepared by a panel of Italian experts. The main objective of this consensus document is to review the scientific evidence related to diagnosis, therapy, and management of patients allergic to hymenoptera venom. Thus, we can improve our knowledge of the disease and promote good clinical practices. The present document provides practical suggestions for correct diagnosis, prescription of emergency therapy and immunotherapy, and strategies for patient care.


Assuntos
Alérgenos/imunologia , Anafilaxia/diagnóstico , Venenos de Artrópodes/imunologia , Dessensibilização Imunológica/métodos , Hipersensibilidade/diagnóstico , Mordeduras e Picadas de Insetos/diagnóstico , Adulto , Anafilaxia/etiologia , Anafilaxia/prevenção & controle , Animais , Criança , Humanos , Himenópteros/imunologia , Hipersensibilidade/complicações , Hipersensibilidade/terapia , Imunoglobulina E/metabolismo , Mordeduras e Picadas de Insetos/complicações , Mordeduras e Picadas de Insetos/terapia , Itália , Guias de Prática Clínica como Assunto , Qualidade de Vida
6.
R Soc Open Sci ; 4(2): 160545, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28386418

RESUMO

The Asian citrus psyllid (Diaphorina citri) is the insect vector responsible for the worldwide spread of 'Candidatus Liberibacter asiaticus' (CLas), the bacterial pathogen associated with citrus greening disease. Developmental changes in the insect vector impact pathogen transmission, such that D. citri transmission of CLas is more efficient when bacteria are acquired by nymphs when compared with adults. We hypothesize that expression changes in the D. citri immune system and commensal microbiota occur during development and regulate vector competency. In support of this hypothesis, more proteins, with greater fold changes, were differentially expressed in response to CLas in adults when compared with nymphs, including insect proteins involved in bacterial adhesion and immunity. Compared with nymphs, adult insects had a higher titre of CLas and the bacterial endosymbionts Wolbachia, Profftella and Carsonella. All Wolbachia and Profftella proteins differentially expressed between nymphs and adults are upregulated in adults, while most differentially expressed Carsonella proteins are upregulated in nymphs. Discovery of protein interaction networks has broad applicability to the study of host-microbe relationships. Using protein interaction reporter technology, a D. citri haemocyanin protein highly upregulated in response to CLas was found to physically interact with the CLas coenzyme A (CoA) biosynthesis enzyme phosphopantothenoylcysteine synthetase/decarboxylase. CLas pantothenate kinase, which catalyses the rate-limiting step of CoA biosynthesis, was found to interact with a D. citri myosin protein. Two Carsonella enzymes involved in histidine and tryptophan biosynthesis were found to physically interact with D. citri proteins. These co-evolved protein interaction networks at the host-microbe interface are highly specific targets for controlling the insect vector responsible for the spread of citrus greening.

7.
J Virol ; 85(5): 2148-66, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21159868

RESUMO

Yellow dwarf viruses in the family Luteoviridae, which are the causal agents of yellow dwarf disease in cereal crops, are each transmitted most efficiently by different species of aphids in a circulative manner that requires the virus to interact with a multitude of aphid proteins. Aphid proteins differentially expressed in F2 Schizaphis graminum genotypes segregating for the ability to transmit Cereal yellow dwarf virus-RPV (CYDV-RPV) were identified using two-dimensional difference gel electrophoresis (DIGE) coupled to either matrix-assisted laser desorption ionization-tandem mass spectrometry or online nanoscale liquid chromatography coupled to electrospray tandem mass spectrometry. A total of 50 protein spots, containing aphid proteins and proteins from the aphid's obligate and maternally inherited bacterial endosymbiont, Buchnera, were identified as differentially expressed between transmission-competent and refractive aphids. Surprisingly, in virus transmission-competent F2 genotypes, the isoelectric points of the Buchnera proteins did not match those in the maternal Buchnera proteome as expected, but instead they aligned with the Buchnera proteome of the transmission-competent paternal parent. Among the aphid proteins identified, many were involved in energy metabolism, membrane trafficking, lipid signaling, and the cytoskeleton. At least eight aphid proteins were expressed as heritable, isoelectric point isoform pairs, one derived from each parental lineage. In the F2 genotypes, the expression of aphid protein isoforms derived from the competent parental lineage aligned with the virus transmission phenotype with high precision. Thus, these isoforms are candidate biomarkers for CYDV-RPV transmission in S. graminum. Our combined genetic and DIGE approach also made it possible to predict where several of the proteins may be expressed in refractive aphids with different barriers to transmission. Twelve proteins were predicted to act in the hindgut of the aphid, while six proteins were predicted to be associated with the accessory salivary glands or hemolymph. Knowledge of the proteins that regulate virus transmission and their predicted locations will aid in understanding the biochemical mechanisms regulating circulative virus transmission in aphids, as well as in identifying new targets to block transmission.


Assuntos
Afídeos/genética , Afídeos/virologia , Proteínas de Bactérias/química , Buchnera/genética , Proteínas de Insetos/química , Luteoviridae/fisiologia , Doenças das Plantas/virologia , Proteômica , Animais , Afídeos/microbiologia , Afídeos/fisiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Buchnera/química , Buchnera/fisiologia , Grão Comestível/virologia , Expressão Gênica , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Dados de Sequência Molecular , Simbiose , Eletroforese em Gel Diferencial Bidimensional
8.
J Insect Physiol ; 57(1): 179-90, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21070785

RESUMO

Homology-driven proteomics promises to reveal functional biology in insects with sparse genome sequence information. A proteomics study comparing plant virus transmission competent and refractive genotypes of the aphid Schizaphis graminum isolated numerous candidate proteins involved in virus transmission, but limited genome sequence information hampered their identification. The complete genome of the pea aphid, Acyrthosiphon pisum, released in 2008, enabled us to double the number of protein identifications beyond what was possible using available EST libraries and other insect sequences. This was concomitant with a dramatic increase of the number of MS and MS/MS peptide spectra matching the genome-derived protein sequence. LC-MS/MS proved to be the most robust method of peptide detection. Cross-matching spectral data to multiple EST sequences and error tolerant searching to identify amino acid substitutions enhanced the percent coverage of the Schizaphis graminum proteins. 2-D electrophoresis provided the protein pI and MW which enabled the refinement of the candidate protein selection and provided a measure of protein abundance when coupled to the spectral data. Thus, the homology-based proteomics pipeline for insects should include efforts to maximize the number of peptide matches to the protein to increase certainty in protein identification and relative protein abundance.


Assuntos
Afídeos/genética , Genoma de Inseto , Proteínas de Insetos/química , Proteínas de Insetos/genética , Proteômica/métodos , Sequência de Aminoácidos , Animais , Afídeos/química , Afídeos/classificação , Afídeos/metabolismo , Bases de Dados de Proteínas , Proteínas de Insetos/metabolismo , Dados de Sequência Molecular , Análise de Sequência de Proteína , Homologia de Sequência de Aminoácidos , Espectrometria de Massas em Tandem
9.
J Biomol Tech ; 20(4): 201-15, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19721822

RESUMO

Protein extraction methods can vary widely in reproducibility and in representation of the total proteome, yet there are limited data comparing protein isolation methods. The methodical comparison of protein isolation methods is the first critical step for proteomic studies. To address this, we compared three methods for isolation, purification, and solubilization of insect proteins. The aphid Schizaphis graminum, an agricultural pest, was the source of insect tissue. Proteins were extracted using TCA in acetone (TCA-acetone), phenol, or multi-detergents in a chaotrope solution. Extracted proteins were solubilized in a multiple chaotrope solution and examined using 1-D and 2-D electrophoresis and compared directly using 2-D Difference Gel Electrophoresis (2-D DIGE). Mass spectrometry was used to identify proteins from each extraction type. We were unable to ascribe the differences in the proteins extracted to particular physical characteristics, cell location, or biological function. The TCA-acetone extraction yielded the greatest amount of protein from aphid tissues. Each extraction method isolated a unique subset of the aphid proteome. The TCA-acetone method was explored further for its quantitative reliability using 2-D DIGE. Principal component analysis showed that little of the variation in the data was a result of technical issues, thus demonstrating that the TCA-acetone extraction is a reliable method for preparing aphid proteins for a quantitative proteomics experiment. These data suggest that although the TCA-acetone method is a suitable method for quantitative aphid proteomics, a combination of extraction approaches is recommended for increasing proteome coverage when using gel-based separation techniques.


Assuntos
Afídeos/química , Eletroforese em Gel de Poliacrilamida/métodos , Proteínas de Insetos/isolamento & purificação , Proteômica/métodos , Acetona , Animais , Carbocianinas/análise , Detergentes , Eletroforese em Gel Bidimensional/métodos , Feminino , Corantes Fluorescentes/análise , Proteínas de Insetos/análise , Espectrometria de Massas , Fenol , Extratos de Tecidos/análise , Ácido Tricloroacético
10.
Eur Ann Allergy Clin Immunol ; 41(1): 23-31, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19496349

RESUMO

BACKGROUND: Different in vivo methods are used to quantify the amount of allergens in products for skin prick testing. It is unclear how this impacts on the correct diagnosis of allergies. AIM OF THE STUDY: We compared the allergenic potency of three commercial extracts for skin prick testing and evaluated batch-to-batch differences within each product. METHODS: Patients with a mono-sensitization (specific IgE level > 0,70 KU/L, ImmunoCAP, Phadia) to Phleum pratense (N=21), Parietaria judaica (N=20) or Dermatophagoides pteronyssinus (N=28) were evaluated by standard skin prick testing and with the end-point dilution technique using commercial products from Stallergenes (A) (Antony, France), Lofarma Allergeni (B) (Milan, Italy) and ALK Abellò (C) (Hoersholm, Denmark). Results were expressed as mean areas of the wheal (cut-off for positive reactions: 7 mm2). RESULTS: With standard prick testing, the following differences in wheal areas were found: Phleum, C higher than B (p=0.0454); Parietaria, C higher than A (p=0.094); Dermatophagoides, C higher than A (p=0.021). With limiting dilution testing, the following differences in dilutions yielding positive skin prick tests were found: Phleum, C and B higher than A (p=0.0391 and 0.0039, respectively); Dermatophagoides, C higher than A and B (p=0.0010 and 0.0156, respectively). In the batch-to-batch comparison, mean differences between wheal areas of compared undiluted solutions did not significantly differ in any allergen tested, although in single cases large differences were observed. At the 1 to 64 dilution, agreement was significant only with Dermatophagoides from Manufacturer C (p= 0.262). At the 1 to 16 dilution, agreement was significant with Phleum from Manufacturer C (p=0.0116) and with Dermatophagoides from Manufacturer B and C (p=0.0239 and 0.0001, respectively). At the 1 to 4 dilution agreement was significant with Dermatophagoides from the three considered Manufacturers (p=0.0189, 0.0052 and 0.0077, respectively) and with Phleum from Manufacturer B and C (p=0.0336 and 0.0113, respectively). CONCLUSION: There are significant differences among commercially available diagnostic products for skin prick testing.


Assuntos
Antígenos de Dermatophagoides , Antígenos de Plantas , Hipersensibilidade/diagnóstico , Testes Cutâneos/métodos , Adolescente , Adulto , Animais , Antígenos de Dermatophagoides/efeitos adversos , Antígenos de Plantas/efeitos adversos , Dermatophagoides pteronyssinus/imunologia , Exposição Ambiental , Feminino , Histamina/imunologia , Histamina/metabolismo , Humanos , Hipersensibilidade/sangue , Imunoglobulina E/sangue , Memória Imunológica , Masculino , Pessoa de Meia-Idade , Parietaria/imunologia , Phleum/imunologia , Reprodutibilidade dos Testes , Fatores Sexuais
12.
Semin Cutan Med Surg ; 22(1): 33-41, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12773012

RESUMO

The histopathological diagnosis of cutaneous melanocytic lesions may be difficult to assess. Frequently encountered diagnostic problems include: 1) Dysplastic nevus or melanoma in situ?; 2) Melanoma in situ or superficial spreading melanoma?; 3) Lentigo maligna or lentigo maligna melanoma?; 4) Compound nevocellular nevus or nevoid melanoma?; and 5) Spitz nevus or Spitzoid melanoma? Moreover, less frequently encountered diagnostic challenges are discussed: 1) Deep penetrating nevus or nodular melanoma?; and 2) Cellular blue nevus or melanoma metastasis? In this contribution, these problems are discussed after a systematic approach involving a concise histopathological description of the classic lesions considered in the differential diagnoses, a presentation of the deviating histopathological features that give rise to the diagnostic problems, and finally diagnostic recommendations on the classification of the problematic lesions. We also briefly discuss the contribution of additional immunohistochemistry and molecular pathology in aiding to establish a correct diagnosis.


Assuntos
Melanoma/patologia , Neoplasias Cutâneas/patologia , Carcinoma in Situ/patologia , Diagnóstico Diferencial , Humanos , Sarda Melanótica de Hutchinson/patologia , Melanoma/classificação , Nevo Azul/patologia , Nevo de Células Epitelioides e Fusiformes/patologia , Nevo Pigmentado/patologia , Neoplasias Cutâneas/classificação
13.
J Pathol ; 198(1): 92-9, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12210068

RESUMO

The plasminogen activation (PA) system is involved in the process of invasion and metastasis. Its major components are urokinase (uPA) and tissue-type plasminogen activator (tPA), plasminogen activation inhibitor type 1 and 2 (PAI-1 and PAI-2) and a receptor for urokinase (uPAR). In this study, the expression of plasminogen activation components in Spitz naevi was compared with that in common and dysplastic naevi on the one hand and primary cutaneous melanomas on the other. Spitz naevi had melanocytic positivity for uPA in 0% (0/36), tPA in 30% (6/20), PAI-1 in 10% (3/35), PAI-2 in 40% (8/21) and uPAR in 60% (13/21) of cases. This far exceeded the expression found in common (n = 25) and dysplastic (n = 15) naevi, which only showed melanocytic positivity for PAI-2 (20% and 15% respectively) and in one dysplastic naevus also for uPAR. This was much (for most components significantly) less than the proportion of primary melanomas with tumour cell positivity, which was 30% (11/38) for uPA, 80% (19/24) for tPA, 75% (28/38) for PAI-1, 80% (19/24) for PAI-2 and 80% (19/24) for uPAR. The main findings of this study are that Spitz naevi, firstly, may express plasminogen activator (tPA), inhibitors and the receptor of the PA system, but in a much smaller proportion than cutaneous melanomas; and secondly, do not express urokinase, whereas some of the melanomas do. uPA positivity may therefore be suggestive of melanoma. However, overlapping staining results imply that the PA system has limited value in the differential diagnosis between Spitz naevus and primary melanoma. As serine protease components are expressed, Spitz naevi may use this proteolytic machinery to accomplish matrix degradation, although in a more restricted, possibly transient manner than melanomas.


Assuntos
Biomarcadores Tumorais/metabolismo , Nevo de Células Epitelioides e Fusiformes/metabolismo , Ativadores de Plasminogênio/metabolismo , Neoplasias Cutâneas/metabolismo , Diagnóstico Diferencial , Síndrome do Nevo Displásico/metabolismo , Síndrome do Nevo Displásico/patologia , Humanos , Técnicas Imunoenzimáticas , Melanoma/diagnóstico , Melanoma/metabolismo , Melanoma/patologia , Nevo de Células Epitelioides e Fusiformes/diagnóstico , Nevo de Células Epitelioides e Fusiformes/patologia , Inativadores de Plasminogênio/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores de Ativador de Plasminogênio Tipo Uroquinase , Inibidores de Serina Proteinase/metabolismo , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Células Estromais/metabolismo , Ativador de Plasminogênio Tecidual/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
15.
Allergy ; 51(9): 658-9, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8899120

RESUMO

PIP: Although copper sulfate can cause systemic contact dermatitis, few such cases have been recorded among copper-releasing IUD users. Reported in this paper is a case of endometritis and urticaria-angioedema syndrome in a 32-year-old user of a copper IUD. Widespread urticaria, as well as angioedema of the eyelids and the labia majora and minora, persisted for about 6 months and were not responsive to corticosteroids and H1-antagonists. Copper sulfate positivity was demonstrated in 72-hour patch test, 48-hour application of the copper spiral to forearm, and in vitro lymphocyte-stimulating test. Histologic examination of the endometrial biopsy revealed vulvovaginitis with hyperplasia of the cervical canal and T-cell and eosinophilic granulocyte infiltration. Removal of the IUD caused complete symptom remission. In experimental animals with a radioactively labeled copper IUD, small amounts of copper sulfate are absorbed through the mucus membrane and carried to the cutis through the blood or lymph. In the cutis, the allergen is intercepted from antigen-presenting cells and recognized by T cells that migrate to the lymph nodes with blastic transformation, proliferation of cytotoxic lymphocytes, and cytokine production.^ieng


Assuntos
Angioedema/etiologia , Dermatite Alérgica de Contato/etiologia , Dispositivos Intrauterinos de Cobre/efeitos adversos , Adulto , Angioedema/diagnóstico , Dermatite Alérgica de Contato/diagnóstico , Feminino , Humanos , Testes do Emplastro
19.
Br J Pharmacol ; 111(4): 1328-32, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8032619

RESUMO

1. Drinking was induced in rats by 24 h of water deprivation. Water intake (ml) was evaluated for a 1 h period. 2. NG-nitro-L-arginine methyl ester (L-NAME, 5-10 micrograms, i.c.v., 50-100 ng into the preoptic area (POA)), an inhibitor of nitric oxide (NO) synthase, and methylene blue (50-100 ng into POA), an inhibitor of guanylate cyclase activation, antagonized the inhibition of drinking induced by E. coli endotoxin (LPS, 640 micrograms kg-1, i.v.) and tumour necrosis factor (TNF alpha, 40 ng, i.c.v.) in 24 h water-deprived rats. 3. L-Arginine (25, 50 and 100 ng), the precursor amino acid of NO, but not the stereoisomer D-arginine (100 ng), inhibited drinking induced by water deprivation when injected into the POA 30 min before water presentation (74.4% of inhibition with the highest dose). A dose of 12.5 ng L-arginine into the POA did not exhibit antidipsogenic effects. 4. TNF alpha (20 and 40 ng, i.c.v.; 1.25, 2.5 and 5 ng into the POA) showed a dose-dependent and powerful inhibition of drinking behaviour in water-deprived rats (70.4% and 80.8%, i.c.v. and into POA, with the highest doses, respectively). A dose of 10 ng of TNF alpha given i.c.v. had no effect on the intake of water. 5. LPS and TNF alpha, given at doses (160 micrograms kg-1, i.v. and 10 ng, i.c.v., respectively) that did not influence drinking in water-deprived rats, exhibited a strong antidipsogenic effect in water-deprived rats treated with a dose of L-arginine (12.5 ng, into the POA) which did not modify drinking by itself. (LPS + L-arginine:53.6% of inhibition; TNFalpha + L-arginine: 52.0% of inhibition).6. These results suggest that NO into the POA: (1) acts as an inhibitory mechanism on thirst and (2)plays a role in the antidipsogenic effect of LPS and TNFalpha.


Assuntos
Ingestão de Líquidos/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Óxido Nítrico/fisiologia , Área Pré-Óptica/fisiologia , Fator de Necrose Tumoral alfa/farmacologia , Animais , Arginina/análogos & derivados , Arginina/farmacologia , Masculino , Azul de Metileno/farmacologia , NG-Nitroarginina Metil Éster , Ratos , Ratos Sprague-Dawley
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