Glutamate is the main excitatory amino acid acting at the level of pre and postsynaptic neurons, as well as in glial cells. It is involved in the coordinated modulation of energy metabolism, glutamine synthesis, and ammonia detoxification. The relationship between the functional status of liver and brain has been known for many years. The most widely recognized aspect of this relation is the brain dysfunction caused by acute liver injury that manifests a wide spectrum of neurologic and psychiatric abnormalities. Inflammation, circulating neurotoxins, and impaired neurotransmission have been reported in this pathophysiology. In the present contribution, we report the effect of a hepatotoxic compound like CCl4 on the expression of key proteins involved in glutamate uptake and metabolism as glutamate transporters and glutamine synthetase in mice liver, brain, and cerebellum. Our findings highlight a differential expression pattern of glutamate transporters in cerebellum. A significant Purkinje cells loss, in parallel to an up-regulation of glutamine synthetase, and astrogliosis in the brain have also been noticed. In the intoxicated liver, glutamate transporter 1 expression is up-regulated, in contrast to glutamine synthetase which is reduced in a time-dependent manner. Taken together our results demonstrate that the exposure to an acute CCl4 insult, leads to the disruption of glutamate transporters expression in the liver-brain axis and therefore a severe alteration in glutamate-mediated neurotransmission might be present in the central nervous system.

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The liver is the organ responsible for bisphenol A (BPA) metabolism, an environmental chemical agent. Exposure to this toxin is associated with liver abnormalities and dysfunction. An important role played by excitatory amino acid transporters (EAATs) of the slc1 gene family has been reported in liver injuries. To gain insight into a plausible effect of BPA exposure in the liver glutamate/aspartate transport, using the human hepatoblastoma cell line HepG2, we report a BPA‐dependent dynamic regulation of SLC1A3 and SLC1A2. Through the use of radioactive [3H]‐ d‐aspartate uptake experiments and immunochemical approaches, we characterized time and dose‐dependent regulation of the protein levels and function of these transporters after acute exposure to BPA. An increase in nuclear Yin Yang 1 was found. These results suggest an important involvement of the EAATs in liver physiology and its disruption after acute BPA exposure.

RESUMEN. Diversos estudios muestran el efecto de la temperatura en la bioacumulación de contaminantes en moluscos bivalvos, pero la inuencia de esté factor en la bioacumulación de hidrocarburos (HC) en Crassostrea virginica no se ha reportado. En este trabajo se estudió el efecto de la temperatura sobre la acumulación de HC en C. virginica en condiciones controladas, la tasa de sobrevivencia (TS) y el desarrollo gametogénico. Se aplicaron cuatro tratamientos con diferentes temperaturas y concentración de HC: A (sin HC a 26 . Mientras que en el tratamiento D se registraron los niveles más altos de HC con 118 mg kg −1 y la TS más baja (53 %). La TS mayor (93 %) se registró en el control y los tratamientos A y C. A nivel celular no se identicó ninguna patología, pero el desarrollo gonádico fue afectado por la presencia de HC y la temperatura de 30• C, con escaso crecimiento gonadal, predominando organismos indenidos. Las diferentes temperaturas no inuyeron en la bioacumulación de HC en los organismos, pero se observa efecto negativo en el desarrollo gametogénico y la TS.Palabras clave: Gametogénesis; molusco; petróleo; sedimento; tasa de sobrevivencia ABSTRACT. Several studies show the eect of temperature on the bioaccumulation of contaminants in bivalve mollusks, but the inuence of this factor on the bioaccumulation of hydrocarbons (HC) in Crassostrea virginica has not been reported. In this work the eect of temperature on HC accumulation in C. virginica under controlled conditions, survival rate (SR) and gametogenic development was studied. Four treatments with dierent temperatures and an HC concentration were studied: A (without HC at 26 , and the lowest SR (53 %). The highest SR (93 %) was recorded in the control and treatments A and C. At the cellular level no pathology was identied, but gonadal development was aected by the presence of HC and the temperature of 30• C, with little gonadal growth and indenite organisms predominating. The dierent temperatures did not inuence HC bioaccumulation in the organisms, but a negative eect on gametogenic development and SR was observed. Colecta de organismosSe obtuvieron de la cooperativa pesquera Del EPA 1994, EPA 1996. Extracción y cuanticación de HC en OrganismosSe realizó la extracción en cada uno de los organismos al término de la exposición. Previamente se llevó a cabo la disección para identicar y extraer las gónadas. Las cuales se jaron en Buer Fosfato Salino con paraformaldehido para histología al 4 % (pH 7.2) hasta su utilización. El resto del organismo se consideró como tejido blando, el cual se empleo para extraer el hidrocarburo acumulado.El tejido se secó en una estufa FELISA a 35• C por 24 h, con la nalidad de eliminar la humedad y obtener el peso neto de cada organismo. Luego se maceró hasta lograr una mezcla homogénea, para realizar la extracción con el método de reujo en un equipo Soxhlet. La cuanticación de HC se realizó calculando el porcentaje de extracto obtenido con la fórmula: % EE = ( P 2−P 1 P m )100 , donde: EE= extracto etéreo, P 2= peso del...