Original Research ARTICLE
GLIAL CELLS ARE INVOLVED IN ANG II- INDUCED VASOPRESSIN RELEASE AND SODIUM INTAKE IN AWAKE RATS.
- 1Biotechnology, Federal University of Paraíba, Brazil
- 2Physiology and Pathology, Health Sciences Center, Federal University of Paraíba, Brazil
- 3Physiology, Ribeirão Preto Medical School, University of São Paulo, Brazil
- 4Physiological Sciences, Biomedical Sciences Institute, Federal University of Alfenas, Brazil
It is known that circulating angiotensin II (ANG-II) acts on the circumventricular organs (CVOs), which partially lack a normal blood-brain barrier, to stimulate pressor response, vasopressin (AVP) and oxytocin (OT) secretion, as well as sodium and water intake. Although, ANG II type 1 receptors (AT1R) are expressed in neurons and astrocytes, the involvement of CVOs glial cells in the neuroendocrine, cardiovascular and behavioral responses induced by central ANG II remains to be further elucidated. To address this question, we performed a set of experiments combining in vitro studies in primary hypothalamic astrocyte cells (HACc) and in vivo intracerebroventricular (icv) microinjections in the lateral ventricle of awake rats. Our results showed that ANG II decreased glutamate uptake in HACc. In addition, in vivo studies showed that fluorocitrate (FCt), a reversible glial inhibitor, increased OT secretion, mean arterial pressure (MAP) and decreased breathing at rest. Furthermore, previous FCt decreased AVP secretion and sodium intake induced by central ANG II. Together, our findings support that CVOs glial cells are important in mediating neuroendocrine and cardiorespiratory functions, as well as, central ANG II- induced AVP release and salt-intake behavior in awake rats. According to our in vitro studies, we propose that these mechanisms are, at least in part, mediated by ANG II-induced astrocyte mediate reduction in glutamate extracellular clearance.
Keywords: central ANG II, glial cells, Pressor response, Neuroendocrine response, drinking behavior.
Received: 09 Feb 2018;
Accepted: 06 Apr 2018.
Edited by:Joaquin Garcia-Estañ, Universidad de Murcia, Spain
Reviewed by:Kathleen S. Curtis, Oklahoma State University Center for Health Sciences, United States
Vicente Lahera, Complutense University of Madrid, Spain
Copyright: © 2018 Flôr, De Brito Alves, França-Silva, Balarini, Elias, Ruginsk, Antunes Rodrigues, Braga and Cruz. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Dr. Josiane C. Cruz, Federal University of Paraíba, Biotechnology, João Pessoa, Paraíba, Brazil, firstname.lastname@example.org