Back to Search
Start Over
Differential control of vasomotion by angiotensins in the rostral ventrolateral medulla of hypertensive rats.
- Source :
-
Neuropeptides [Neuropeptides] 2015 Oct; Vol. 53, pp. 11-8. Date of Electronic Publication: 2015 Sep 09. - Publication Year :
- 2015
-
Abstract
- The central and peripheral renin-angiotensin systems are known for playing a key role in cardiovascular control. In the present study, we evaluated the hemodynamic effects produced by nanoinjections of angiotensin II (Ang II) or angiotensin-(1-7) [Ang-(1-7)] into the rostral ventrolateral medulla (RVLM) of adult male normotensive (Wistar-WT) and spontaneously hypertensive rats (SHR). Animals were anesthetized (urethane 1.2g/kg) and instrumented for recording blood pressure (BP), heart rate (HR) and blood flow (BF) in the femoral, renal or mesenteric arteries. Afterwards, rats were positioned in a stereotaxic and prepared for nanoinjections (100 nl) of saline (NaCl 0.9%), Ang-(1-7) (40 ng) or Ang II (40 ng) into the RVLM. The vascular resistance (VR) was calculated by ΔMAP/ΔBF ratio. In WT, Ang-(1-7) or Ang II caused equipotent pressor effects that were not accompanied by changes in vascular resistance. However, MAP changes were greater in SHR. This strain also showed a concomitant increase in relative vascular resistance (ΔVR/VRbaseline) of renal (0.31 ± 0.07 and 0.3 ± 0.07 vs. 0.02 ± 0.01; Ang-(1-7), Ang II and Saline, respectively) and mesenteric beds (0.3 ± 0.06 and 0.33 ± 0.04 vs. 0.05 ± 0.02; Ang-(1-7), Ang II and saline, respectively). We conclude that Ang II and Ang-(1-7) at the RVLM control the vascular resistance of renal and mesenteric beds during hypertension.<br /> (Copyright © 2015 Elsevier Ltd. All rights reserved.)
- Subjects :
- Animals
Arterial Pressure drug effects
Blood Pressure drug effects
Cardiac Output drug effects
Cerebrovascular Circulation drug effects
Heart Rate drug effects
Male
Mesenteric Arteries drug effects
Rats
Rats, Inbred SHR
Rats, Wistar
Regional Blood Flow drug effects
Splanchnic Circulation drug effects
Vascular Resistance drug effects
Angiotensin I pharmacology
Angiotensin II pharmacology
Medulla Oblongata blood supply
Medulla Oblongata drug effects
Peptide Fragments pharmacology
Subjects
Details
- Language :
- English
- ISSN :
- 1532-2785
- Volume :
- 53
- Database :
- MEDLINE
- Journal :
- Neuropeptides
- Publication Type :
- Academic Journal
- Accession number :
- 26390943
- Full Text :
- https://doi.org/10.1016/j.npep.2015.09.002