RESUMO
Perinatal asphyxia (PA) affects the synaptic function and morphological organization. In previous works, we have shown neuronal and synaptic changes in rat neostriatum subjected to hypoxia leading to long-term ubi-protein accumulation. Since F-actin is highly concentrated in dendritic spines, modifications in its organization could be related with alterations induced by hypoxia in the central nervous system (CNS). In the present study, we investigate the effects of PA on the actin cytoskeleton of hippocampal postsynaptic densities (PSD) in 4-month-old rats. PSD showed an increment in their thickness and in the level of ubiquitination. Correlative fluorescence-electron microscopy photooxidation showed a decrease in the number of F-actin-stained spines in hippocampal excitatory synapses subjected to PA. Although western blot analysis also showed a slight decrease in ß-actin in PSD in PA animals, the difference was not significant. Taken together, this data suggests that long-term actin cytoskeleton might have role in PSD alterations which would be a spread phenomenon induced by PA.
Assuntos
Asfixia/patologia , Espinhas Dendríticas/patologia , Hipocampo/patologia , Animais , Animais Recém-Nascidos , Espinhas Dendríticas/ultraestrutura , Feminino , Hipocampo/ultraestrutura , Masculino , Gravidez , Ratos , Ratos Sprague-DawleyRESUMO
Treatment of male Wistar rats with hexachlorobenzene (HCB) (1000 mg/kg b.w.) for 3-30 days decreases circulating levels of thyroxine (T4) but does not affect triiodothyronine (T3). Time courses were determined for 5' deiodinase type I (5' D-I) activity in thyroid, liver, and kidney and 5' deiodinase type II (5' D-II) activity in brown adipose tissue (BAT) to test the possibility that increased deiodinase activity might contribute to the maintenance of the serum T3 level. Specific 5' D-I activity was increased in the thyroid at 21 days and thereafter. No significant changes were observed in the liver, however, total 5' D-I activity in this tissue was increased at 30 days of treatment as a consequence of liver weight enhancement. HCB decreased kidney 5' D-I activity after 15 days, and BAT 5' D-II activity after 21 days of treatment. Total body 5' D-I activity was significantly increased by 30 days of HCB-treatment. HCB increased the activity of hepatic T4 uridine diphosphoglucuronosyl transferase (UDPGT) in a time-dependent manner, without changes in T3 UDPGT. We propose that increased T4 to T3 conversion in the thyroid and in the greatly enlarged liver may account for the maintenance of serum T3 concentration in hypothyroxinemic HCB-treated rats.
Assuntos
Poluentes Ambientais/toxicidade , Hexaclorobenzeno/toxicidade , Iodeto Peroxidase/metabolismo , Doenças da Glândula Tireoide/induzido quimicamente , Glândula Tireoide/efeitos dos fármacos , Hormônios Tireóideos/metabolismo , Tecido Adiposo Marrom/efeitos dos fármacos , Tecido Adiposo Marrom/enzimologia , Administração Oral , Animais , Poluentes Ambientais/administração & dosagem , Fungicidas Industriais/administração & dosagem , Expressão Gênica/efeitos dos fármacos , Glucuronosiltransferase/metabolismo , Hexaclorobenzeno/administração & dosagem , Iodeto Peroxidase/genética , Rim/efeitos dos fármacos , Rim/enzimologia , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Doenças da Glândula Tireoide/sangue , Glândula Tireoide/enzimologia , Hormônios Tireóideos/análiseRESUMO
The effect of the in vivo administration of hexachlorobenzene (HCB) (100 mg/100 g bw) for 30 days, on the activities of brown adipose tissue (BAT) lipogenic enzymes, i.e. malic enzyme (ME), and glucose-6-phosphate dehydrogenase (G6PD) and the mitochondrial non lipogenic enzyme, L-glycerol-3-phosphate dehydrogenase (LG3PD), was studied in male Wistar rats, submitted to various neurohormonal manipulations. BAT ME, G6PD and LG3PD activities showed significant reductions in response to HCB treatment both in euthyroid and surgically thyroidectomized rats, showing that the effect does not depend on the presence of thyroid hormones. These results differ from those obtained for hepatic ME and G6PD activities, which increased in HCB intoxicated rats without alteration in LG3PD. HCB decreased BAT ME activity under BAT denervation. Administration of HCB resulted in time and dose-dependent decreases in the activity of BAT malic enzyme. The basal activity of ME was increased in hypothyroid rats, while that of LG3PD was reduced. A stimulatory effect of receptor-saturating doses of triiodothyronine (T3) (50 microg/100 g body weight) was observed on BAT ME and LG3PD activities in thyroidectomized rats, showing that the enzymes responded to thyroid hormone stimulation in a normal manner. The stimulatory effect of saturating doses of T3 on ME and LG3PD was reduced by HCB. The results presented herein unequivocally show that brown adipose tissue is a specific target in HCB-induced toxicity, which in turn involves severe alterations in the regulation of BAT lipogenesis.
Assuntos
Tecido Adiposo Marrom/enzimologia , Glicerolfosfato Desidrogenase/metabolismo , Hexaclorobenzeno/farmacologia , Lipídeos/biossíntese , NADP/biossíntese , Tecido Adiposo Marrom/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/enzimologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Wistar , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/enzimologia , Tiroxina/sangue , Tri-Iodotironina/sangueRESUMO
El objetivo de este trabajo es evaluar la seroprevalencia del Chagas y de la Toxoplasmosis en mujeres embarazadas. Se estudiaron 290 mujeres en un período de 3 meses que fueron controladas durante su embarazo en la Maternidad del Hospital Ramos Mejia de la ciudad de Buenos Aires. La detección de toxoplasmosis y de Chagas fue realizado midiendo en todas las pacientes inmunoglobulina G y M, por métodos de inmunofluorescencia y hemoaglutinación indirecta. La seroprevalencia de toxoplasmosis fue de 39.31 por ciento de las cuales 2.63 por ciento presentaron infección aguda y fueron tratadas durante el embarazo. La seroprevalencia de Chagas fue de 9.66 por ciento. Concluimos que este estudio nos muestra la importancia de estas enfermedades en la población embarazada y el control que hay que tener sobre ellas
Assuntos
Adolescente , Adulto , Humanos , Feminino , Gravidez , Doença de Chagas/epidemiologia , Doença de Chagas/etiologia , Complicações Infecciosas na Gravidez , Primeiro Trimestre da Gravidez , Testes Sorológicos , Toxoplasmose , ArgentinaRESUMO
El objetivo de este trabajo es evaluar la seroprevalencia del Chagas y de la Toxoplasmosis en mujeres embarazadas. Se estudiaron 290 mujeres en un período de 3 meses que fueron controladas durante su embarazo en la Maternidad del Hospital Ramos Mejia de la ciudad de Buenos Aires. La detección de toxoplasmosis y de Chagas fue realizado midiendo en todas las pacientes inmunoglobulina G y M, por métodos de inmunofluorescencia y hemoaglutinación indirecta. La seroprevalencia de toxoplasmosis fue de 39.31 por ciento de las cuales 2.63 por ciento presentaron infección aguda y fueron tratadas durante el embarazo. La seroprevalencia de Chagas fue de 9.66 por ciento. Concluimos que este estudio nos muestra la importancia de estas enfermedades en la población embarazada y el control que hay que tener sobre ellas
