PMID- 28833692 OWN - NLM STAT- MEDLINE DCOM- 20180709 LR - 20211204 IS - 1469-445X (Electronic) IS - 0958-0670 (Linking) VI - 102 IP - 11 DP - 2017 Nov 1 TI - Central angiotensin-(1-7) increases osmotic thirst. PG - 1397-1404 LID - 10.1113/EP086417 [doi] AB - What is the central question of this study? The central goal of this study was to understand the effects of central angiotensin-(1-7) on basal and osmotically stimulated water intake in rats. What is the main finding and its importance? This study demonstrated that central administration of angiotensin-(1-7) did not induce thirst in basal conditions but increased water intake after osmotic stimulation, such as water deprivation and salt loading. These results indicate a new function for this peptide, which, in turn, allows for future research on the mechanisms through which angiotensin-(1-7) influences osmotic thirst. Angiotensin-(1-7) [Ang-(1-7)] is generated by type 2 angiotensin-converting enzyme (ACE2) and binds to the MAS receptor. Although it is well known that Ang-(1-7) functionally antagonizes the effects of the classical renin-angiotensin system in several situations, the role of Ang-(1-7) in hydromineral homeostasis is not clear. The aim of this study was to assess the role of Ang-(1-7) on neuroendocrine responses to hyperosmolality in rats. Male Wistar rats were divided into the following three groups: control; 24 h of water deprivation (WD); and 24 h of salt loading (SL; 1.8% NaCl). Intracerebroventricular (i.c.v.) injections of Ang-(1-7) or vehicle were given to assess water intake and plasma concentration of vasopressin. Additionally, the brains from control and WD groups were collected to evaluate gene expression in the subfornical organ (SFO), paraventricular nucleus (PVN) and supraoptic nucleus (SON). It was found that i.c.v. Ang-(1-7) did not change water and salt intake in control rats; however, Ang-(1-7) increased water intake after WD and SL, with no change in salt intake. Plasma vasopressin was not changed by i.c.v. Ang-(1-7) in control or WD rats. Moreover, WD increased Mas gene expression in the SON and PVN, with no changes in Ace2 mRNA levels. In conclusion, Ang-(1-7) increases thirst after osmotic stimuli, indicating that a previous sensitization to its action is necessary. This finding is consistent with the increased Mas gene expression in the PVN and SON after water deprivation. CI - (c) 2017 The Authors. Experimental Physiology (c) 2017 The Physiological Society. FAU - Dos-Santos, Raoni Conceicao AU - Dos-Santos RC AUID- ORCID: 0000-0001-9675-754X AD - Department of Physiological Sciences, Institute of Biological and Health Sciences, Federal Rural University of Rio de Janeiro, Seropedica, Rio de Janeiro, Brazil. FAU - Monteiro, Livia da Rocha Natalino AU - Monteiro LDRN AD - Department of Physiological Sciences, Institute of Biological and Health Sciences, Federal Rural University of Rio de Janeiro, Seropedica, Rio de Janeiro, Brazil. FAU - Paes-Leme, Bruno AU - Paes-Leme B AUID- ORCID: 0000-0002-2976-6523 AD - Department of Physiological Sciences, Institute of Biological and Health Sciences, Federal Rural University of Rio de Janeiro, Seropedica, Rio de Janeiro, Brazil. FAU - Lustrino, Danilo AU - Lustrino D AD - Department of Physiology, Federal University of Sergipe, Aracaju, Sergipe, Brazil. FAU - Antunes-Rodrigues, Jose AU - Antunes-Rodrigues J AD - Department of Physiology, Ribeirao Preto School of Medicine, Sao Paulo University, Ribeirao Preto, Sao Paulo, Brazil. FAU - Mecawi, Andre Souza AU - Mecawi AS AD - Department of Physiological Sciences, Institute of Biological and Health Sciences, Federal Rural University of Rio de Janeiro, Seropedica, Rio de Janeiro, Brazil. FAU - Reis, Luis Carlos AU - Reis LC AD - Department of Physiological Sciences, Institute of Biological and Health Sciences, Federal Rural University of Rio de Janeiro, Seropedica, Rio de Janeiro, Brazil. LA - eng PT - Journal Article DEP - 20171004 PL - England TA - Exp Physiol JT - Experimental physiology JID - 9002940 RN - 0 (Peptide Fragments) RN - 0 (Proto-Oncogene Mas) RN - 0 (Proto-Oncogene Proteins) RN - 0 (Receptors, G-Protein-Coupled) RN - 11000-17-2 (Vasopressins) RN - 451W47IQ8X (Sodium Chloride) RN - 9041-90-1 (Angiotensin I) RN - EC 3.4.15.1 (Peptidyl-Dipeptidase A) RN - EC 3.4.17.23 (Ace2 protein, rat) RN - EC 3.4.17.23 (Angiotensin-Converting Enzyme 2) RN - IJ3FUK8MOF (angiotensin I (1-7)) SB - IM MH - Angiotensin I/*administration & dosage MH - Angiotensin-Converting Enzyme 2 MH - Animals MH - Drinking/*drug effects MH - Injections, Intraventricular MH - Male MH - *Osmotic Pressure MH - Paraventricular Hypothalamic Nucleus/*drug effects/metabolism MH - Peptide Fragments/*administration & dosage MH - Peptidyl-Dipeptidase A/genetics/metabolism MH - Proto-Oncogene Mas MH - Proto-Oncogene Proteins/genetics/metabolism MH - Rats, Wistar MH - Receptors, G-Protein-Coupled/genetics/metabolism MH - Sodium Chloride/administration & dosage MH - Subfornical Organ/*drug effects/metabolism MH - Supraoptic Nucleus/*drug effects/metabolism MH - Thirst/*drug effects MH - Up-Regulation MH - Vasopressins/blood MH - Water Deprivation OTO - NOTNLM OT - angiotensin OT - salt loading OT - water deprivation EDAT- 2017/08/24 06:00 MHDA- 2018/07/10 06:00 CRDT- 2017/08/24 06:00 PHST- 2017/04/19 00:00 [received] PHST- 2017/08/18 00:00 [accepted] PHST- 2017/08/24 06:00 [pubmed] PHST- 2018/07/10 06:00 [medline] PHST- 2017/08/24 06:00 [entrez] AID - 10.1113/EP086417 [doi] PST - ppublish SO - Exp Physiol. 2017 Nov 1;102(11):1397-1404. doi: 10.1113/EP086417. Epub 2017 Oct 4.