RESUMEN
INTRODUCTION: Exposure to noise stress during early life may permanently affect the structure and function of the central nervous system. The aim of this study was to evaluate the effects of prenatal exposure to urban traffic noise on the spatial learning and memory of the rats' offspring and the expression of glucocorticoid receptors (GRs) in their hippocampi. METHODS: Three g\roups of pregnant rats were exposed to recorded urban traffic noise for 1, 2 or 4 h/day during the last week of pregnancy. At the age of 45 days, their male offspring were introduced to the Morris water maze (MWM) for assessment of spatial learning and memory. The corticosterone levels were measured in the offspring's sera by radioimmunoassay, and the relative expression of glucocorticoid and mineralocorticoid receptors (MRs) in their hippocampi was evaluated via RT-PCR. RESULTS: Facing urban traffic noise for 2 and 4 h/day during the third trimester of pregnancy caused the offspring to spend more time and to travel a larger distance than the controls to find the target platform. Analogously, these two groups were inferior to their control counterparts in the probe test. Also, prenatal noise stress elevated the corticosterone concentration in the sera of the rats' offspring and dose-dependently decreased the relative expression of the mRNA of both GRs and MRs in their hippocampi. CONCLUSIONS: Urban traffic noise exposure during the last trimester of pregnancy impairs spatial learning and memory of rat offspring and reduces GRs and MRs gene expression in the hippocampus.
Asunto(s)
Hipocampo/fisiología , Discapacidades para el Aprendizaje/etiología , Trastornos de la Memoria/patología , Ruido del Transporte/efectos adversos , Efectos Tardíos de la Exposición Prenatal/etiología , Receptores de Glucocorticoides/biosíntesis , Aprendizaje Espacial/fisiología , Animales , Animales Recién Nacidos , Femenino , Regulación de la Expresión Génica , Hipocampo/embriología , Hipocampo/metabolismo , Discapacidades para el Aprendizaje/metabolismo , Discapacidades para el Aprendizaje/patología , Masculino , Aprendizaje por Laberinto , Trastornos de la Memoria/etiología , Trastornos de la Memoria/metabolismo , Modelos Animales , Embarazo , Ratas , Ratas Wistar , Receptores de Glucocorticoides/metabolismoRESUMEN
Decreasing the side effects of chemotherapy in testis has been the subjects of many studies. In this study, the protective effects of Zingiber officinale extract on rat testis were investigated after chemotherapy with cyclophosphamide. Histological and biochemical parameters were compared in cyclophosphamide-treated rats with or without ginger extract intake. Wistar male rats were randomly divided into four groups each 10. The control group received a single injection of 1 ml isotonic saline intraperitoneally. The Cyclophosphamide (CP) group received a single dose of cyclophosphamide (100 mg kg(-1) BW) intraperitoneally. CP + 300 and CP + 600 groups received orally 300 or 600 mg of ginger extract, respectively, for a period of 6 weeks after cyclophosphamide injection. The morphologic and histological structure of the testis was compared in different groups of the rats. Also, factors like malondialdehyde, reactive oxygen species, total antioxidant capacity and testosterone level were assessed in blood serum as well. Our results showed that although ginger extract could not change testis weight, malondialdehyde (MDA) and ROS, but antioxidant and testosterone levels in serum were increased significantly. Also, an obvious improved histological change was seen in CP + 300 and CP + 600 groups in comparison with CP group. These protective effects of ginger on rat testis after cyclophosphamide treatment could be attributed to the higher serum level of antioxidants.