Item Type: | Article |
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Title: | Improved cardiovascular autonomic modulation in transgenic rats expressing an Ang-(1-7)-producing fusion protein |
Creators Name: | Dartora, D.R., Irigoyen, M.C., Casali, K.R., Moraes-Silva, I.C., Bertagnolli, M., Bader, M. and Santos, R. |
Abstract: | Angiotensin-(1-7) counterbalances Angiotensin II cardiovascular effects. However, it has yet to be determined how cardiovascular autonomic modulation may be affected by chronic and acute elevation of Ang-(1-7). Hemodynamics and cardiovascular autonomic profile were evaluated in male Sprague-Dawley (SD) and transgenic rats (TGR) overexpressing Ang-(1-7) [TGR(A1-7)3292]. Blood pressure (BP) was directly measured while cardiovascular autonomic modulation was evaluated by spectral analysis. TGR received A-779 or vehicle and SD rats received Ang-(1-7) or vehicle and were monitored for 5 hours after i.v. administration. In another set of experiments with TGR, A-779 was infused for 7 days using osmotic mini pumps. Although at baseline no differences were observed, acute administration of A-779 in TGR produced a marked long lasting increase in BP accompannied by increased BP variability (BPV) and sympathetic modulation to the vessels. Likewise, chronic administration of A-779 with osmotic mini pumps in TGR increased heart rate, sympathovagal balance, BPV and sympathetic modulation to the vessels. Administration of Ang-(1-7) to SD rats increased HRV values in 88% accompannied by 8% of vagal modulation increase and 18% of mean BP reduction. These results show that both acute and chronic alteration in the Ang-(1-7)-Mas receptor axis may lead to important changes in the autonomic control of circulation, impacting either sympathetic and/or parasympathetic systems. |
Keywords: | Renin-Angiotensin System, Angiotensin-(1-7), A-779, Blood Pressure, Autonomic Nervous System, Heart Rate Variability, Spectral Analysis, Animals, Rats |
Source: | Canadian Journal of Physiology and Pharmacology |
ISSN: | 0008-4212 |
Publisher: | National Research Council Press |
Volume: | 95 |
Number: | 9 |
Page Range: | 993-998 |
Date: | September 2017 |
Additional Information: | Copyright © The Author(s) 2017. |
Official Publication: | https://doi.org/10.1139/cjpp-2016-0557 |
External Fulltext: | View full text on external repository or document server |
PubMed: | View item in PubMed |
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