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1.
J Oral Rehabil ; 36(1): 39-44, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18976260

RESUMO

The aim was to validate self-perceived oral health with salivary IgG as an inflammatory parameter in children with type 1 diabetes. Unstimulated whole saliva samples were collected from 36 children with well controlled and 12 with poorly controlled type 1 diabetes and 40 non-diabetic children (Controls). Salivary flow rate, random blood glucose level, salivary protein concentration and immunoglobulin A and G levels were recorded using standard techniques. Data concerning oral health and diabetes status were collected. Self-perceived gingival bleeding (bleeding gums), bad breath and dry mouth were higher in diabetic children when compared with those in controls (P < 0.05). Gingival bleeding was frequently perceived by children with poorly controlled compared to well-controlled type 1 diabetes (P < 0.05) and controls (P < 0.001). Bad breath was common perceived by children with poorly controlled compared to well-controlled type 1 diabetes (P < 0.05) and controls (P < 0.0001). Salivary flow rate was lower in the diabetic children compared to controls (P < 0.01) with no difference between children with poorly controlled and well-controlled type 1 diabetes. Salivary IgG per mg protein concentration was higher in the diabetics when compared with the control group (P < 0.0001). IgG per mg protein levels were also higher in children with poorly controlled when compared with well-controlled type 1 diabetes (P < 0.05). There was no difference in IgA per mg protein and total protein concentrations between children with poorly controlled and well-controlled type 1 diabetes. Self-perceived gingival bleeding and salivary IgG per mg protein concentration were increased in children with type 1 diabetes compared with controls. These variables were also increased in children with poorly controlled compared with well-controlled type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Hemorragia Gengival/complicações , Conhecimentos, Atitudes e Prática em Saúde , Imunoglobulina G/metabolismo , Saúde Bucal , Saliva/metabolismo , Adolescente , Glicemia/metabolismo , Estudos de Casos e Controles , Criança , Inquéritos de Saúde Bucal , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/psicologia , Hemorragia Gengival/imunologia , Hemorragia Gengival/metabolismo , Hemorragia Gengival/psicologia , Hemoglobinas Glicadas/metabolismo , Nível de Saúde , Humanos , Imunoglobulina A/metabolismo , Valores de Referência , Saliva/imunologia , Proteínas e Peptídeos Salivares/imunologia , Proteínas e Peptídeos Salivares/metabolismo , Autoimagem , Autoavaliação (Psicologia) , Xerostomia/complicações , Xerostomia/imunologia , Xerostomia/metabolismo , Xerostomia/psicologia , Adulto Jovem
2.
Ann Rheum Dis ; 65(4): 453-8, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16176994

RESUMO

OBJECTIVE: To evaluate the significance of antibodies against cyclic citrullinated peptide (anti-CCP) and rheumatoid factors (RFs), before the onset of rheumatoid arthritis and when presenting as early disease (baseline), for disease activity and progression. METHODS: 93 of a cohort of 138 patients with early rheumatoid arthritis (<12 months of symptoms) had donated blood before symptoms of rheumatoid arthritis (defined as pre-patients) and were identified from among blood donors within the Medical Biobank of northern Sweden. Disease activity (erythrocyte sedimentation rate (ESR), C reactive protein, joint score, global visual analogue scale) and radiological destruction in hands and feet (Larsen score) were assessed at baseline and after two years. Anti-CCP antibodies and RFs were analysed using enzyme immunoassays. HLA shared epitope (SE) alleles (DRB1*0401/0404) were identified. RESULTS: Patients with anti-CCP antibodies before disease onset had significantly higher Larsen score at baseline and after two years. In multiple regression analyses baseline values of anti-CCP/IgA-RF/IgG-RF/IgM-RF, swollen joint count, and Larsen score significantly predicted radiological outcome at two years. In logistic regression analyses, baseline values of anti-CCP antibodies/IgA-RF, therapeutic response at six months, and swollen joint count/ESR significantly predicted radiological progression after two years. The baseline titre of anti-CCP antibodies was higher in patients with radiological progression and decreased significantly in those with response to therapy. SE allele carriage was associated with a positive test for anti-CCP antibodies in pre-patients and in early rheumatoid arthritis. CONCLUSIONS: Presence of anti-CCP antibodies before disease onset is associated with more severe radiological damage. The titre of anti-CCP antibodies is related to disease severity.


Assuntos
Artrite Reumatoide/diagnóstico , Autoanticorpos/sangue , Peptídeos Cíclicos/imunologia , Fator Reumatoide/sangue , Adulto , Idoso , Artrite Reumatoide/diagnóstico por imagem , Biomarcadores/sangue , Sedimentação Sanguínea , Progressão da Doença , Ensaio de Imunoadsorção Enzimática/métodos , Métodos Epidemiológicos , Feminino , Humanos , Imunoglobulina A/sangue , Masculino , Pessoa de Meia-Idade , Prognóstico , Radiografia , Índice de Gravidade de Doença
3.
Clin Exp Immunol ; 112(2): 341-6, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9649200

RESUMO

Patients with IgA deficiency often demonstrate circulating antibodies against IgA, which have been suggested to be associated with transfusion reactions. Sera from three patients with common variable immunodeficiency (CVID) and one with a selective IgA deficiency with anti-IgA antibodies receiving subcutaneous gammaglobulin replacement therapy were analysed for serum levels of IgG, IgA and anti-IgA before and during a treatment period of 4-7 years. Treatment with gammaglobulin preparations containing significant amounts of IgA (< 5 mg/ml) resulted in a decrease or disappearance of the anti-IgA antibodies. Analysis of serum fractions, however, revealed anti-IgA activity in the complex-containing fractions. In vitro experiments gave similar results with a shift of anti-IgA activity from the monomeric to the complex-containing fractions (that could not be detected in whole serum). When the patients were subsequently switched to treatment with a preparation containing less IgA (< 80 microg/ml) or made an interruption in the treatment schedule, the anti-IgA antibodies reappeared. Importantly, however, one of the patients lost his anti-IgA activity during a 3-month period on the preparation containing the higher IgA levels, and these antibodies did not reappear after switching to the low IgA-containing preparation. After 5 years on this preparation, anti-IgA can still not be detected, suggesting induction of unresponsiveness.


Assuntos
Imunodeficiência de Variável Comum/imunologia , Deficiência de IgA/imunologia , Imunização Passiva , Imunoglobulina A/imunologia , Adulto , Anticorpos Anti-Idiotípicos/análise , Cromatografia em Gel , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Tolerância Imunológica , Imunoglobulina A/análise , Imunoglobulina G/análise , Masculino
4.
Acta Paediatr ; 84(12): 1386-94, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8645957

RESUMO

To estimate the prevalence of chronic granulomatous disease (CGD) in Sweden, an inquiry asking for known and possible CGD cases was mailed to paediatric, internal medicine and infectious disease departments all over Sweden. The detected patients were characterized as to genetics and the clinical presentation. Twenty-one patients (belonging to 16 different families) were found, corresponding to a prevalence of approximately 1/450,000 individuals. The patients with X-linked disease, lacking a functional gp91phox protein (n = 12), comprised 57% and 43% of the patients had an autosomal recessive (AR) disease lacking p47phox (n = 7) or p67phox (n = 1), respectively. All unrelated patients with X-linked disease displayed different gene abnormalities such as point mutations predicting nonsense (n = 3), missense (n = 1) or splice site mutations (n = 2), but also a total deletion and a unique 40 base pair duplicature insertion. The patients with p47phox-deficiency showed a GT deletion at a GTGT tandem repeat, and the p67phox-deficient patient displayed a heterozygous in-frame deletion of AAG combined with a large deletion in the other allele. Three patients died during the study period, two from pseudomonas cepacia infections. Patients with X-linked disease had more frequent infections (mean of 1.7 per year), than the patients with AR inheritance (0.5 infections per year). The most common infections were dermal abscesses (n = 111), followed by lymphadenitis (n = 82) and pneumonias (n = 73). Inflammatory bowel disease-like symptoms, mimicking Crohn's disease of the colon, was seen in three CGD patients.


Assuntos
Doença Granulomatosa Crônica/genética , Adolescente , Adulto , Criança , Pré-Escolar , Aberrações Cromossômicas/genética , Transtornos Cromossômicos , Estudos Transversais , Feminino , Genes Recessivos/genética , Triagem de Portadores Genéticos , Ligação Genética/genética , Doença Granulomatosa Crônica/diagnóstico , Doença Granulomatosa Crônica/epidemiologia , Humanos , Incidência , Masculino , Infecções Oportunistas/diagnóstico , Infecções Oportunistas/epidemiologia , Infecções Oportunistas/genética , Mutação Puntual/genética , Fatores de Risco , Aberrações dos Cromossomos Sexuais/genética , Suécia/epidemiologia , Cromossomo X
6.
Eur J Haematol ; 51(4): 218-22, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7694872

RESUMO

Chronic granulomatous disease (CGD) is characterized by the inability of the patients' phagocytic leukocytes to generate superoxide. Therefore, these cells fail to kill certain bacteria and fungi. As a result, patients with CGD suffer from recurrent, life-threatening infections with these micro-organisms. Superoxide is produced by NADPH oxidase, a multicomponent enzyme exclusively present in phagocytic leukocytes. The most common form of CGD is X-linked, originating from a deficiency of the high-molecular-weight subunit of cytochrome b558 (gp91-phox). Here we describe a patient suffering from X-linked CGD due to a 40-base-pair duplication in exon 7 of the CYBB gene coding for gp91-phox, predicting a frameshift, substitution of 22 amino acids and a premature stop codon at amino-acid position 253. The mother as well as the grandmother of this patient were proven to be heterozygous for this mutation; the father and sister were normal. However, the great-grandmother proved to have normal oxidative functions, suggesting that the mutation occurred three generations ago. This is the first description of a nucleotide duplication leading to CGD.


Assuntos
Grupo dos Citocromos b/genética , Doença Granulomatosa Crônica/genética , Leucócitos Mononucleares/metabolismo , NADPH Oxidases , Mutação Puntual , Cromossomo X , Sequência de Aminoácidos , Sequência de Bases , Northern Blotting , Éxons , Feminino , Doença Granulomatosa Crônica/sangue , Humanos , Lactente , Íntrons , Substâncias Macromoleculares , Masculino , Dados de Sequência Molecular , Família Multigênica , Linhagem , Reação em Cadeia da Polimerase/métodos , RNA/sangue , RNA/isolamento & purificação , Mapeamento por Restrição
7.
Immunology ; 77(4): 604-8, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1493932

RESUMO

The class and subclass distribution of antibodies against gliadin in intestinal lavage fluid, saliva and serum was investigated in individuals with coeliac disease. Serum antibodies against gliadin were mainly or even exclusively of the IgA1 subclass. In intestinal lavage fluid and saliva, antibodies of both IgA1 and IgA2 subclasses were found. In patients with and without IgA deficiency, an IgG response was detected both in serum and intestinal lavage fluid with a predominance of IgG1 in selected patients. Specific IgG2, IgG3 and IgG4 antibodies were also detected in intestinal lavage fluid, while no specific IgG2, IgG3 or IgG4 antibodies were found in serum, suggesting a local production of specific IgG antibodies. In Western blot analysis, intestinal lavage fluid and serum IgA antibodies reacted against gliadin components with a MW between 33,000 and 42,000. Serum IgA1 antibodies directed against a gliadin component with a MW slightly higher than 42,000 were also observed. Specific IgG and IgM antibodies in both the secretion and serum against gliadin components with a MW between 33,000 and 42,000 were also detected. This study shows that mucosa-derived gliadin-specific IgA and IgG antibodies may be produced even when there is an absence of specific antibodies of the corresponding immunoglobulin subclass in serum. Furthermore, the specificity of serum and intestinal lavage fluid anti-gliadin IgA1 antibodies may differ.


Assuntos
Doença Celíaca/imunologia , Gliadina/imunologia , Imunoglobulina A/análise , Imunoglobulina G/análise , Mucosa Intestinal/imunologia , Especificidade de Anticorpos/imunologia , Western Blotting , Humanos , Saliva/imunologia
8.
Scand J Gastroenterol ; 27(2): 124-8, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1561525

RESUMO

Primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) are characterized by immunoregulatory disturbances and fibrosis. Several cytokines may be of importance for the inflammatory response and the development of fibrosis. In the present study the capacity to produce tumor necrosis factor (TNF) and interleukin-1 (IL-1) was determined in 11 patients with PSC, 10 patients with PBC, and 20 healthy control subjects. As compared with the controls, in vitro cultured mononuclear cells from PBC patients showed a lower spontaneous TNF production (median, 16,499 cpm; range, 7181-41,907; p less than 0.02), whereas the TNF production of PSC patients was similar to that of the controls. Lipopolysaccharide (LPS)-stimulated TNF production was also lower in the PBC group (median, 40,564 cpm; range, 23,493-69,452) than in PSC patients (median, 58,898 cpm; range, 37,997-91,485; p less than 0.03). The spontaneous and LPS-stimulated IL-1 production did not differ in patients and healthy controls. The cytokine production in patients with PBC and PSC did not correlate to histologic activity, associated diseases such as ulcerative colitis and bilirubin, or to Child-Pugh classification. Thus, in contrast to hepatocellular diseases, in which cytokine production is reported to be increased, PBC and PSC are accompanied by low or normal TNF and IL-1 production.


Assuntos
Colangite Esclerosante/metabolismo , Interleucina-1/biossíntese , Cirrose Hepática Biliar/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Células Cultivadas , Humanos , Lipopolissacarídeos/administração & dosagem
9.
Clin Exp Immunol ; 83(3): 407-12, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1848490

RESUMO

Antibody reactivity against the 'mitochondrial M2 antigen' was determined in sera from 10 patients with primary biliary cirrhosis (PBC), using Western blotting after SDS-PAGE separation of rat liver mitochondria (RLM) and plasma membrane proteins. The molecular weights of the major M2 antigens in rat liver mitochondria were 67 and 50 kD. Two of the 10 PBC patients did not react to any of these major antigens, eight reacted to the 67-kD and four of those also to the 50-kD antigen. The 67- and 50-kD antigens were present in both plasma membrane and RLM and had affinity to concanavalin A. Antibody reactivity against the 67-kD antigen could be detected in both IgG and IgA as well as in the IgM class. The reactive IgG subclasses to both types of antigen preparations were mainly of the G1 and G3 isotypes. This reactivity was always stronger with antigens from the plasma membrane preparations. Sera from two patients with high antibody titres against mitochondria also reacted with IgG2 against the 50-kD antigen from plasma membrane, but not to the corresponding antigen in mitochondria. Reactivity of antibodies in PBC sera to the periphery of viable hepatocytes and radioactive surface labelling of the 50-kD component are both consistent with a plasma membrane localization of M2. Serum from healthy controls and several patients with different diseases did not contain antibodies reactive against any of the antigens described. We suggest that antigens, partly identical to the mitochondrial M2, are located in the plasma membrane compartment. The PBC pathogenetical consequences of these findings are discussed.


Assuntos
Autoantígenos/análise , Membrana Celular/imunologia , Cirrose Hepática Biliar/imunologia , Mitocôndrias/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Western Blotting , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Eletroforese em Gel de Poliacrilamida , Feminino , Imunofluorescência , Cobaias , Humanos , Imunoglobulina G/imunologia , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Mitocôndrias Hepáticas/imunologia , Ratos
10.
Clin Exp Immunol ; 81(2): 238-43, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2387091

RESUMO

Autoantibodies reactive against mitochondria which are present in sera from patients with primary biliary cirrhosis (PBC) have been shown to bind to the lipoamide acetyltransferase moiety (E2) of the pyruvate dehydrogenase enzyme complex (PDH). This newly described antigen has been shown to be identical to M2, a 70-kD antigen of the inner mitochondrial membrane. Sera from 10 patients with PBC, 11 patients with chronic active hepatitis (CAH), 20 healthy controls and patients with thyroiditis and systemic lupus erythematosus (SLE) were tested by ELISA for the presence of antibodies (IgG and IgM classes and IgG subclasses) reactive against PDH. The effect of serum and separated IgG and IgM on the PDH enzyme activity was measured spectrophotometrically. Nine out of 10 PBC sera were positive by immunofluorescence for mitochondria (M2 pattern). These nine sera reacted strongly with both IgG and IgM to PDH in the ELISA and also inhibited the enzyme activity by 80% (s.d. 25%). This was significantly different compared with the controls (4 +/- 6%; P less than 0.001). Enzyme inhibition was mainly caused by IgG. Of all control sera (from healthy and patient individuals) only one patient with CAH reacted significantly in the tests. This CAH patient had a high antibody titre against mitochondria as measured by immunofluorescence.


Assuntos
Autoanticorpos/imunologia , Doenças Autoimunes/imunologia , Cirrose Hepática Biliar/imunologia , Complexo Piruvato Desidrogenase/antagonistas & inibidores , Doenças Autoimunes/enzimologia , Cromatografia/métodos , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Cirrose Hepática Biliar/enzimologia , Mitocôndrias Hepáticas/imunologia , Complexo Piruvato Desidrogenase/imunologia
11.
Brain Behav Immun ; 3(4): 345-58, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2611415

RESUMO

Antibody reactivity to rat brain components in sera from schizophrenic patients and healthy controls was determined using ELISA and Western immunoblotting. Crude membranes prepared from striatum, hippocampus and cortex were used as antigens. The degree of ELISA reactivity varied between individuals but no significant difference was seen between the patient and control groups in any of the different preparations. With a blocking-type of ELISA, in which a pool of dopamine receptor antagonists/neuroleptica was used to compete with the antibody binding, inhibition of IgG reactivity was seen in half of the patient and a quarter of the control sera. When the antagonists were added individually, 25% of the patients but none of the controls showed an inhibited IgG response due to haloperidol and sulpiride. In Western immunoblotting there was a complex background pattern overlaid with a variety of individual bands that could not be related to disease. However a few bands specific for the schizophrenic group were found in more than 50% of the patients. The molecular weights of the two most prominent polypeptides were 86 and 68 kD. The three major Ig-classes G, A, and M showed a partly overlapping and variable degree of reactivity in the patient group. By screening, it was found that 3 out of 50 control sera reacted with either the 86 or the 68 Kd polypeptide. The results do not exclude the possibility that schizophrenic patients do have antibodies reactive to the dopamine receptor.


Assuntos
Autoanticorpos/imunologia , Encéfalo/imunologia , Proteínas do Tecido Nervoso/imunologia , Esquizofrenia/imunologia , Adulto , Animais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Immunoblotting , Masculino , Ratos , Ratos Endogâmicos
12.
Clin Exp Immunol ; 74(2): 276-82, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3265656

RESUMO

The antibody reactivity to liver specific protein (LSP) and a crude liver antigen of sera from patients with chronic active hepatitis (CAH) were studied along with other related diseases and healthy individuals. CAH sera containing liver reacting antibodies were selected using an ELISA with a crude liver preparation as antigen and subsequently the specificity was analysed by immunoblotting of SDS-PAGE-separated LSP. The incidence of IgG antibodies to the crude liver antigen and LSP in sera from 15 patients with CAH was 94% and 55% respectively. In the healthy control group (n = 30) the corresponding figures were 3% and 17%. Sera from patients with other autoimmune conditions with considerable reactivity in the crude liver ELISA test were those with antibodies against extractable nuclear antigens (ENA) and thyroid gland antigens, while the anti-nuclear antibody (ANA) group as a whole did not differ from the control group. In immunoblotting of SDS-PAGE-separated crude liver and LSP antigens, the IgG binding pattern of ELISA IgG positive CAH sera and sera from patients with thyroid disease was distinct, with bands corresponding to antigens of molecular weights of 38, 45 and 50 kD which were not observed in ELISA negative CAH sera or in sera from patients with other diseases and among healthy controls.


Assuntos
Hepatite Crônica/imunologia , Imunoglobulina G/imunologia , Proteínas de Membrana , Adolescente , Adulto , Anticorpos Antinucleares/análise , Reações Antígeno-Anticorpo , Antígenos de Superfície/imunologia , Western Blotting , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Rim/imunologia , Fígado/imunologia , Masculino , Pessoa de Meia-Idade , Mitocôndrias Hepáticas/imunologia , Proteínas/imunologia
13.
Am J Physiol ; 252(5 Pt 2): R822-32, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-3107404

RESUMO

To investigate the acclimation process in a hibernator, four different parameters of thermogenin amount and activity were investigated in brown adipose tissue mitochondria from cold-exposed and cold-acclimated Syrian hamsters. Hamsters, which are hibernators, have been considered to be "primed" for thermogenesis and thus not to show cold-acclimation effects, but here a significant increase in [3H]GDP-binding capacity was observed (from 0.5 nmol in control to 0.9 nmol GDP/mg in cold-acclimated hamsters), and this increase was paralleled by an increase in thermogenin antigen amount, as measured in an enzyme-linked immunosorbent assay. The transient nature of the effect of cold exposure on [3H]GDP binding, characteristically observed with rat mitochondria, was not observed with hamster mitochondria, and the increase in [3H]GDP binding occurred without a change in the dissociation constant (0.7 microM). The increase in thermogenin amount was paralleled by an increase both in GDP-sensitive Cl- permeability of the mitochondria and in GDP-sensitive respiration. It was established that it is the maximal activity of thermogenin that is rate limiting for thermogenesis in isolated mitochondria, provided that an optimal substrate is used (such as palmitoyl carnitine). Cold acclimation also increased the total amount of mitochondria in the tissue, leading totally to a sixfold increase in thermogenin content of the hamster. It is concluded that (contrary to the general view) hamsters show the expected physiological, pharmacological, and biochemical signs of cold acclimation (i.e., an increased capacity for nonshivering thermogenesis).


Assuntos
Aclimatação , Tecido Adiposo Marrom/metabolismo , Proteínas de Transporte/metabolismo , Temperatura Baixa , Proteínas de Membrana , Mitocôndrias/metabolismo , Tecido Adiposo Marrom/ultraestrutura , Animais , Cloretos/metabolismo , Cricetinae , Ensaio de Imunoadsorção Enzimática , Guanosina Difosfato/metabolismo , Canais Iônicos , Mesocricetus , Proteínas Mitocondriais , Consumo de Oxigênio , Permeabilidade , Proteína Desacopladora 1
14.
Metabolism ; 33(11): 1028-33, 1984 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6092828

RESUMO

The effects of hyperthyroidism and hypothyroidism on the metabolism of adipocytes isolated from rat brown adipose tissue were as follows: The yield of brown adipocytes was 65% less in the hypothyroid as compared to the control rats. No change in cell recovery was observed in the hyperthyroid group as compared to controls but there was a 65% increase in cell volume. The stimulation of respiration by isoproterenol and forskolin was markedly greater in cells from hyperthyroid as compared to euthyroid rats. In the adipocytes from hypothyroid rats, respiration and lipolysis were reduced but there was no defect in stimulation of adenylate cyclase by forskolin or isoproterenol as compared to euthyroid controls. The effects of different thyroid states on respiration did not correlate with changes in adenosine 3':5'-cyclic phosphate (cyclic AMP) or lipolysis. Phenylephrine in the presence of alprenolol or octanoate were as potent stimulators of respiration as 10 mumol/L isoproterenol in adipocytes from hypothyroid rats. In cells from hyperthyroid rats phenylephrine was twice, octanoate three times, and isoproterenol 16 times more effective in stimulating respiration than in cells from hypothyroid rats. These data indicate that thyroid status regulates beta-catecholamine and forskolin stimulation of respiration in brown adipocytes.


Assuntos
Tecido Adiposo Marrom/metabolismo , Catecolaminas/fisiologia , Hormônios Tireóideos/fisiologia , Adenilil Ciclases/metabolismo , Animais , Caprilatos/farmacologia , Colforsina , AMP Cíclico/metabolismo , Diterpenos/farmacologia , Ácidos Graxos não Esterificados/metabolismo , Feminino , Hipertireoidismo/metabolismo , Hipotireoidismo/metabolismo , Técnicas In Vitro , Isoproterenol/farmacologia , Lipólise/efeitos dos fármacos , Tamanho do Órgão , Consumo de Oxigênio/efeitos dos fármacos , Fenilefrina/farmacologia , Ligação Proteica , Ratos
15.
Artigo em Inglês | MEDLINE | ID: mdl-6520042

RESUMO

Groups of rats were subjected to various treatments: continuous exposure to cold (5 degrees C); exercise by running; intermittent cold exposure, -20 degrees C daily for 60 min; and in some experiments combined influence of cold acclimation and exercise for at least 6 wk. The resulting adaptive changes can be grouped in three different categories. Cold-specific changes included increased food intake, an increase in both mass and metabolic activity of brown adipose tissue leading to an increased capacity for nonshivering thermogenesis, and maintenance of the stores of ascorbic acid and muscle glycogen during cold exposure. These changes were associated with an improved resistance to cold with which the rats were able to maintain their body temperature in both cold air and water were typical of rats previously exposed to cold. Training-specific changes typically included increased activities of aerobic muscle enzymes and decreased activity of lactate dehydrogenase and a higher O2 uptake and shivering activity during cold exposure as compared with sedentary control rats. These changes were observed for trained rats only and were not associated with an improved resistance to cold. Other adaptive changes were found, to a variable extent, for all treated rat groups. These included cardiac hypertrophy, reduced urinary catecholamine excretion during and after stress situations, increased tail skin temperature response to isoproterenol, and a higher tail skin temperature during exposure to cold. There were no systematic differences between groups in changes of blood glucose, glycerol, or lactate concentrations during cold exposure.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Adaptação Fisiológica , Temperatura Baixa , Atividade Motora/fisiologia , Tecido Adiposo Marrom/metabolismo , Animais , Temperatura Corporal/efeitos dos fármacos , Peso Corporal , Colo , Isoproterenol/farmacologia , Masculino , Músculos/metabolismo , Tamanho do Órgão , Oxirredução , Ratos , Ratos Endogâmicos , Temperatura Cutânea/efeitos dos fármacos , Estresse Fisiológico/metabolismo
17.
Am J Physiol ; 244(3): C142-9, 1983 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6299108

RESUMO

Brown adipose tissue has earlier been suggested as an important site of the diet-induced thermogenesis that results from cafeteria feeding in rats. The aim of the present communication has been to see if any defined component of this diet can mimic the effects of the diet on the trophic response of brown fat and if these effects are mediated by the sympathetic nervous system. Rats fed a lipid emulsion did not show hypertrophy of brown adipose tissue. Rats fed a glucose solution, whether voluntarily or by force feeding, showed a clear trophic response of brown fat, as seen by the morphology of the tissue and its increased wet weight, increased protein content, increased total and specific cytochrome c oxidase activity, and increased mitochondrial guanosine diphosphate binding. Chemical sympathectomy of young rats by guanethidine prior to glucose feeding impaired the glucose-induced effects on brown fat. beta-Adrenergic blockade in adult rats also tended to depress the glucose effect. Consequently we conclude that chronic glucose ingestion can mimic cafeteria feeding with respect to the trophic response of brown fat and that an intact sympathetic nervous system is required for the mediation of the glucose effect to the brown adipose tissue.


Assuntos
Tecido Adiposo Marrom/efeitos dos fármacos , Glucose/farmacologia , Sistema Nervoso Simpático/fisiologia , Tecido Adiposo Marrom/metabolismo , Animais , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Guanetidina , Guanosina Difosfato/metabolismo , Mitocôndrias/metabolismo , Propranolol/farmacologia , Ratos , Ratos Endogâmicos , Simpatectomia , Simpatectomia Química
18.
Am J Physiol ; 241(3): C134-9, 1981 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7282915

RESUMO

Reports on a reciprocal relationship between sympathetic-nerve and experimentally induced changes in thyroid-hormone activity called into question the proposed role of thyroxine in the changes seen in the brown fat after cold adaptation. Rats reared at +30, +22, and +5 degrees C received daily injections of thyroxine (1 mg/kg). After 3 wk of treatment, the thermogenic state of the tissue was assessed by measuring the capacity of the brown fat mitochondria to bind guanosine 5'-diphosphate (GDP). GDP-inhibited mitochondrial swelling, brown adipose tissue (BAT) wet weights, and mitochondrial yields were also measured. The control animals showed a linear increase in GDP binding between +30 and +5 degrees C. Thyroxine was found to lower the GDP binding markedly at +5 degrees C, less so at +22 degrees C, while no effect was evident at +30 degrees C. The values at +22 and +30 degrees C were identical. The other parameters studied all confirmed these results. The conclusion made is that the thyroxine-induced rise in basal metabolic rate lowers the critical temperature and reduces the demand for nonshivering thermogenesis. This is reflected in the reduced GDP binding and hence heating capacity of the brown fat mitochondria.


Assuntos
Tecido Adiposo Marrom/metabolismo , Nucleotídeos de Guanina/metabolismo , Guanosina Difosfato/metabolismo , Mitocôndrias/metabolismo , Tiroxina/farmacologia , Animais , Peso Corporal , Feminino , Cinética , Mitocôndrias/efeitos dos fármacos , Dilatação Mitocondrial , Ratos , Ratos Endogâmicos , Temperatura
19.
Biol Neonate ; 39(3-4): 142-9, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7295835

RESUMO

The thermogenic capacity of brown fat from neonatal and developing hamsters was investigated. The method used was to measure the capacity of brown fat mitochondria to bind externally added guanosine diphosphate (GDP). This gives an estimate of the number of proton-conducting channels and hence the capacity of heat production in the mitochondria. At an age of 12 days post-partum the GDP-binding capacity is low: 0.14 nmol GDP/mg mitochondrial protein. Thereafter the capacity shows a steady increase up to 0.54 nmol/mg at 20 days. The peak is followed by a slow decrease down to the level of the adult hamster: 0.32 nmol/mg. this pattern of brown fat development is strikingly similar to reports on the development of oxygen consumption measured on whole animals or on the ability to maintain a constant body temperature when the ambient temperature is lowered. The calorigenic response to injected noradrenaline also follows this pattern. It is therefore justified to suggest that brown fat is a major effector of regulative metabolic heat production in the developing hamster.


Assuntos
Tecido Adiposo Marrom/fisiologia , Regulação da Temperatura Corporal , Nucleotídeos de Guanina/metabolismo , Guanosina Difosfato/metabolismo , Tecido Adiposo Marrom/anatomia & histologia , Envelhecimento , Animais , Animais Recém-Nascidos , Cricetinae , Feminino , Mesocricetus , Mitocôndrias/fisiologia , Peso Molecular , Tamanho do Órgão , Gravidez , Proteínas/fisiologia
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