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Parras de la Fuente, Mexico

Leon-Olea M.,Instituto Nacional Of Psiquiatria | Martyniuk C.J.,University of New Brunswick | Orlando E.F.,University of Maryland University College | Ottinger M.A.,University of Maryland University College | And 4 more authors.
General and Comparative Endocrinology | Year: 2014

In the last few years, it has become clear that a wide variety of environmental contaminants have specific effects on neuroendocrine systems in fish, amphibians, birds and mammals. While it is beyond the scope of this review to provide a comprehensive examination of all of these neuroendocrine disruptors, we will focus on select representative examples. Organochlorine pesticides bioaccumulate in neuroendocrine areas of the brain that directly regulate GnRH neurons, thereby altering the expression of genes downstream of GnRH signaling. Organochlorine pesticides can also agonize or antagonize hormone receptors, adversely affecting crosstalk between neurotransmitter systems. The impacts of polychlorinated biphenyls are varied and in many cases subtle. This is particularly true for neuroedocrine and behavioral effects of exposure. These effects impact sexual differentiation of the hypothalamic-pituitary-gonadal axis, and other neuroendocrine systems regulating the thyroid, metabolic, and stress axes and their physiological responses. Weakly estrogenic and anti-androgenic pollutants such as bisphenol A, phthalates, phytochemicals, and the fungicide vinclozolin can lead to severe and widespread neuroendocrine disruptions in discrete brain regions, including the hippocampus, amygdala, and hypothalamus, resulting in behavioral changes in a wide range of species. Behavioral features that have been shown to be affected by one or more these chemicals include cognitive deficits, heightened anxiety or anxiety-like, sociosexual, locomotor, and appetitive behaviors. Neuroactive pharmaceuticals are now widely detected in aquatic environments and water supplies through the release of wastewater treatment plant effluents. The antidepressant fluoxetine is one such pharmaceutical neuroendocrine disruptor. Fluoxetine is a selective serotonin reuptake inhibitor that can affect multiple neuroendocrine pathways and behavioral circuits, including disruptive effects on reproduction and feeding in fish. There is growing evidence for the association between environmental contaminant exposures and diseases with strong neuroendocrine components, for example decreased fecundity, neurodegeneration, and cardiac disease. It is critical to consider the timing of exposures of neuroendocrine disruptors because embryonic stages of central nervous system development are exquisitely sensitive to adverse effects. There is also evidence for epigenetic and transgenerational neuroendocrine disrupting effects of some pollutants. We must now consider the impacts of neuroendocrine disruptors on reproduction, development, growth and behaviors, and the population consequences for evolutionary change in an increasingly contaminated world. This review examines the evidence to date that various so-called neuroendocrine disruptors can induce such effects often at environmentally-relevant concentrations. © 2014 Elsevier Inc. Source

Hamann S.,Copenhagen University | Herrera-Perez J.J.,Instituto Nacional Of Psiquiatria | Zeuthen T.,Copenhagen University | Alvarez-Leefmans F.J.,Wright State University
Journal of Physiology | Year: 2010

Water transport by the Na+-K+-2Cl cotransporter (NKCC1) was studied in confluent cultures of pigmented epithelial (PE) cells from the ciliary body of the fetal human eye. Interdependence among water, Na+ and Cl fluxes mediated by NKCC1 was inferred from changes in cell water volume, monitored by intracellular self-quenching of the fluorescent dye calcein. Isosmotic removal of external Cl or Na+ caused a rapid efflux of water from the cells, which was inhibited by bumetanide (10 μm). When returned to the control solution there was a rapid water influx that required the simultaneous presence of external Na+ and Cl. The water influx could proceed uphill, against a transmembrane osmotic gradient, suggesting that energy contained in the ion fluxes can be transferred to the water flux. The influx of water induced by changes in external [Cl] saturated in a sigmoidal fashion with a Km of 60 mm, while that induced by changes in external [Na+] followed first order kinetics with a Km of about 40 mm. These parameters are consistent with ion transport mediated by NKCC1. Our findings support a previous investigation, in which we showed water transport by NKCC1 to be a result of a balance between ionic and osmotic gradients. The coupling between salt and water transport in NKCC1 represents a novel aspect of cellular water homeostasis where cells can change their volume independently of the direction of an osmotic gradient across the membrane. This has relevance for both epithelial and symmetrical cells.Cell volume control is fundamental for cell survival. Cells have evolved mechanisms for maintaining their volume constant. These mechanisms involve the movement of solutes and water across the plasma membrane through specialized proteins. The water within a cell ultimately determines its volume and has been assumed to cross the cell membrane exclusively through channels called aquaporins. We show that water also crosses the membrane carried by NKCC1, a membrane protein belonging to the Na+-K+-Cl cotransporter (NKCC) family. This membrane protein transports 1 sodium, 1 potassium and 2 chloride ions together with a large number of water molecules per cycle. A key finding is that NKCC1 transports water uphill, against an osmotic gradient. These observations increase our knowledge of how cells and tissues handle water, and are important for understanding medical conditions like brain oedema, intracranial hypertension, glaucoma and airway hydration disorders. © 2010 The Authors. Journal compilation © 2010 The Physiological Society. Source

Solis-Chagoyan H.,Instituto Nacional Of Psiquiatria | Alvarado R.,National Autonomous University of Mexico | Figueroa A.,National Autonomous University of Mexico | Mendoza-Vargas L.,National Autonomous University of Mexico | Fuentes-Pardo B.,National Autonomous University of Mexico
Comparative Biochemistry and Physiology - A Molecular and Integrative Physiology | Year: 2012

In crayfish, one very well-studied circadian rhythm is that of electroretinogram (ERG) amplitude. The cerebroid ganglion has been considered a plausible site for the circadian pacemaker of this rhythm and for the retinular photoreceptors, as the corresponding effectors. The pigment dispersing hormone (PDH) appears to synchronize ERG rhythm, but its characterization as a synchronizer cue remains incomplete. The main purposes of this work were a) to determine whether PDH acts on the cerebroid ganglion, and b) to complete its characterization as a non-photic synchronizer. Here we show that PDH increases the number of the spontaneous potentials of the cerebroid ganglion, reaching 149.92. ±. 6.42% of the activity recorded in the controls, and that daily application of PDH for 15 consecutive days adjusts the ERG circadian rhythm period to 24.0. ±. 0.2. h and the end of the activity period of the rhythm coincides with the injection of the hormone. In this work, we hypothesized that in crayfish, PDH transmits the "day" signal to the ERG circadian system and acts upon both the presumptive circadian pacemaker and the corresponding effectors to reinforce the synchronization of the system. © 2012 Elsevier Inc.. Source

Mercadillo R.E.,National Autonomous University of Mexico | Alcauter S.,University of North Carolina at Chapel Hill | Alcauter S.,Instituto Nacional Of Psiquiatria | Fernandez-Ruiz J.,National Autonomous University of Mexico | Barrios F.A.,National Autonomous University of Mexico
Social Neuroscience | Year: 2015

Compassion is a prototypical moral emotion supporting cooperation and involves empathic decision-making and motor processes representing the interplay of biologically evolved and cultural mechanisms. We propose a social neuroscience approach to identify gender differences and to assess biological and cultural factors shaping compassion. We consider the police force as a cultural model to study this emotion, because it comprises a mixed-gender group using specific codes for collective safety that influence empathy and cooperativeness. From a sample of Mexican police officers working in a violent environment we integrated ethnographic data categorizing compassionate elements in the officers’ activities, psychometric measures evaluating empathic attitudes, and fMRI scans identifying the brain activity related to compassionate experiences and decisions. The results suggest that the police culture influences genders equally with respect to empathic behavioral expressions. Nevertheless, women showed insular and prefrontal cortical activation, suggesting a more empathic experience of compassion. Officers manifested activity in the caudate nucleus, amygdala, and cerebellum, suggesting a more a highly accurate process to infer another’s suffering and a reward system motivated by the notion of service and cooperation, both of which are cultural traits represented in the police force. © 2014 Taylor & Francis. Source

de la Fuente-Sandoval C.,Instituto Nacional Of Neurologia Y Neurocirugia | Favila R.,General Electric | Gomez-Martin D.,Instituto Nacional Of Nutricion | Pellicer F.,Instituto Nacional Of Psiquiatria | Graff-Guerrero A.,Multimodal Neuroimaging Schizophrenia Group
Psychiatry Research - Neuroimaging | Year: 2010

Clinical evidence suggests that there is decreased pain sensitivity in schizophrenia; however, the neurobiological mechanism of this decrease remains unknown. Using functional magnetic resonance imaging, we examined the blood oxygen level-dependent (BOLD) changes induced by experimental pain-tolerance (endure) hot stimuli vs. non-painful stimuli during an acute psychotic episode in 12 drug-free patients with schizophrenia and in 13 gender- and age-matched healthy controls. The analyses revealed that patients showed a greater BOLD response at S1 compared with controls but a reduced BOLD response in the posterior cingulate cortex (PCC), insula, and brainstem during pain-tolerance stimuli. Pain-tolerance temperature was higher in patients than in healthy controls. BOLD response in the insula positively correlated with unpleasantness and temperature in controls, but this effect was not observed in patients. S1 BOLD response positively correlated with unpleasantness in patients but not in controls. These initial results confirm that unmedicated patients with schizophrenia have a higher pain tolerance than controls, decreased activation in pain affective-cognitive processing regions (insula, PCC, brainstem), and an over-activation of the primary sensory-discriminative pain processing region (S1). These pilot results are the first to explore the mechanism driving altered pain sensitivity in schizophrenia. © 2010 Elsevier Ireland Ltd. Source

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