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1.
Arch Environ Contam Toxicol ; 59(4): 642-51, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20372884

RESUMEN

Many insectivores have been shown to be sensitive to heavy metals and therefore suitable for biomonitoring purposes. In Finland, the hibernation period of the European hedgehog (Erinaceus europaeus) is long, and during hibernation the stress caused by environmental toxins may be crucial. Concentrations of cadmium (Cd), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), arsenic (As), and selenium (Se) were measured in a population of hedgehogs in the town of Joensuu in eastern Finland during the summers of 2004 and 2005. The analyzed tissues were kidney, liver, hair, and spine. The sampled hedgehogs (n = 65) were mainly road-killed animals. As expected, the concentrations of heavy metals were low because the hedgehogs were living in a comparatively unpolluted area. Significant increases with age were found in Cd concentrations (kidney, liver, and spine) and some essential elements (Se in spine, kidney, and liver; Mo in kidney and liver; Cu in spine; Fe in liver; and Mn in spine). Age accumulation and correlations between Se and Cd and between Mo and Cd may indicate the protective roles of Se and Mo against Cd toxicity in hedgehogs, in which Cd is already at comparatively low concentrations. Sex had no significant effect on concentrations of the elements studied. In conclusion, age is an important parameter to be taken into account when studying heavy-metal concentrations in hedgehogs and other insectivores.


Asunto(s)
Arsénico/metabolismo , Contaminantes Ambientales/metabolismo , Erizos/metabolismo , Metales/metabolismo , Selenio/metabolismo , Factores de Edad , Animales , Exposición a Riesgos Ambientales/estadística & datos numéricos , Monitoreo del Ambiente , Femenino , Cabello/metabolismo , Riñón/metabolismo , Hígado/metabolismo , Masculino , Factores Sexuales , Columna Vertebral/metabolismo
2.
Toxicol Appl Pharmacol ; 202(2): 132-9, 2005 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-15629188

RESUMEN

The aim of the present study was to examine the reproductive effects of two perorally applied phytoestrogens, genistein (8 mg/kg/day) and beta-sitosterol (50 mg/kg/day), on the mink (Mustela vison) at human dietary exposure levels. Parental generations were exposed over 9 months to these phytoestrogens and their offspring were exposed via gestation and lactation. Parents and their offspring were sampled 21 days after the birth of the kits. Sex hormone levels, sperm quality, organ weights, and development of the kits were examined. The exposed females were heavier than the control females at the 1st postnatal day (PND). The control kits were heavier than the exposed kits from the 1st to the 21st PND. Phytoestrogens did not affect the organ weights of the adult minks, but the relative testicular weight of the exposed kits was higher than in the control kits. The relative prostate weight was higher and the relative uterine weight lower in the beta-sitosterol-exposed kits than in the control kits. Moreover, the plasma dihydrotestosterone levels were lower in the genistein-exposed male kits compared to the control male kits. This study could not explain the mechanisms behind these alterations. The results indicate that perinatal phytoestrogen exposures cause alterations in the weight of the reproductive organs of the mink kits.


Asunto(s)
Genitales Femeninos/efectos de los fármacos , Genitales Masculinos/efectos de los fármacos , Visón/fisiología , Fitoestrógenos/farmacología , Administración Oral , Envejecimiento , Animales , Animales Recién Nacidos/anatomía & histología , Animales Recién Nacidos/sangre , Índice de Masa Corporal , Dihidrotestosterona/sangre , Esquema de Medicación , Estradiol/sangre , Femenino , Finlandia , Genitales Femeninos/anatomía & histología , Genitales Femeninos/fisiología , Genitales Masculinos/anatomía & histología , Genitales Masculinos/fisiología , Hormonas Esteroides Gonadales/sangre , Hormonas Esteroides Gonadales/farmacología , Masculino , Visón/anatomía & histología , Tamaño de los Órganos/efectos de los fármacos , Tamaño de los Órganos/fisiología , Fitoestrógenos/química , Embarazo , Efectos Tardíos de la Exposición Prenatal , Reproducción/efectos de los fármacos , Reproducción/fisiología , Semen/química , Semen/efectos de los fármacos , Caracteres Sexuales , Sitoesteroles/farmacología , Especificidad de la Especie , Recuento de Espermatozoides/métodos , Testículo/química , Testículo/efectos de los fármacos , Testosterona/sangre
3.
Exp Biol Med (Maywood) ; 228(2): 188-93, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12563026

RESUMEN

Phytosterols or plant sterols (PS) enter the ecosystem via pulp mill effluents. They are also consumed by the general population of developed countries in natural remedies and margarines to lower elevated serum cholesterol levels. This study screened the endocrine and enzymatic parameters of the field vole (Microtus agrestis) for the effects of subchronic PS exposure at three doses (0, 5, or 50 mg of PS kg(-1) day(-1)). PS at 5 or 50 mg kg(-1) day(-1) decreased the relative liver weight of the voles. The kidney glycogen phosphorylase activity decreased at 5 or 50 mg kg(-1) day(-1), but the liver glycogen phosphorylase activity increased at 5 mg kg(-1) day(-1). The plasma estradiol and testosterone concentrations of males were higher due to PS supplement at 5 mg kg(-1) day(-1). This can be due to increased sex steroid synthesis from PS precursors. Biotransformation enzyme activities were not affected. PS caused multiple, previously unreported effects that were more pronounced at a low dose. As 5 mg PS kg(-1) day(-1) is the recommended dose for various health products, a thorough risk assessment of the effects and interactions of PS is warranted.


Asunto(s)
Arvicolinae/metabolismo , Riñón/enzimología , Hígado/enzimología , Fitosteroles/metabolismo , Animales , Peso Corporal , Metabolismo de los Hidratos de Carbono , Ingestión de Alimentos , Femenino , Hormonas Esteroides Gonadales/sangre , Humanos , Metabolismo de los Lípidos , Masculino , Tamaño de los Órganos , Radioinmunoensayo , Distribución Aleatoria
4.
Toxicol Appl Pharmacol ; 178(1): 22-8, 2002 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-11781076

RESUMEN

Phytosterols or plant sterols (PS) are consumed as natural remedies and margarines by the general population in developed countries to lower elevated serum cholesterol levels. They are also present in high concentrations in pulp mill effluents. The aim of the study was to screen the endocrine and metabolic parameters of the European polecat (Mustela putorius) for the effects of PS. The results showed an increase in the plasma estradiol and TH levels with no effects on the hypophyseal regulatory hormones. The plasma ghrelin levels decreased. PS also affected intermediary metabolism. The liver glycogen content increased as did the kidney glucose-6-phosphatase activity. The liver lipase esterase activity, on the other hand, decreased due to PS. In serum lipids the total cholesterol did not change, but the low-density lipoprotein levels increased and the high-density lipoprotein-cholesterol ratio decreased. PS had widespread previously unreported effects on the physiology of the polecat. The multiple effects indicate the need of a thorough risk assessment of the effects and interactions of PS.


Asunto(s)
Carnívoros/metabolismo , Glándulas Endocrinas/metabolismo , Isoflavonas , Fitosteroles/farmacología , Animales , Peso Corporal/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Glándulas Endocrinas/efectos de los fármacos , Congéneres del Estradiol/farmacología , Estrógenos no Esteroides/farmacología , Femenino , Glucógeno/metabolismo , Hormonas/sangre , Hipolipemiantes/farmacología , Inactivación Metabólica , Riñón/efectos de los fármacos , Riñón/metabolismo , Lípidos/sangre , Hígado/efectos de los fármacos , Hígado/enzimología , Masculino , Metabolismo/efectos de los fármacos , Tamaño de los Órganos/efectos de los fármacos , Fitoestrógenos , Preparaciones de Plantas , Sitoesteroles/farmacología
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