Work

High salt diet impairs cerebral blood flow regulation via salt‐induced angiotensin II suppression

Year: 2018

Type: article

Abstract: OBJECTIVES: This study sought to determine whether salt-induced ANG II suppression contributes to impaired CBF autoregulation. METHODS: Cerebral autoregulation was evaluated with LDF during graded reductions of blood pressure. Autoregulatory responses in rats fed HS (4% NaCl) diet vs LS (0.4% NaCl) diet were analyzed using linear regression analysis, model-free analysis, and a mechanistic theoretical model of blood flow through cerebral arterioles. RESULTS: Autoregulation was intact in LS-fed animals as MAP was reduced via graded hemorrhage to approximately 50 mm Hg. Short-term (3 days) and chronic (4 weeks) HS diet impaired CBF autoregulation, as evidenced by progressive reductions of laser Doppler flux with arterial pressure reduction. Chronic low dose ANG II infusion (5 mg/kg/min, i.v.) restored CBF autoregulation between the pre-hemorrhage MAP and 50 mm Hg in rats fed short-term HS diet. Mechanistic-based model analysis showed a reduced myogenic response and reduced baseline VSM tone with short-term HS diet, which was restored by ANG II infusion. CONCLUSIONS: Short-term and chronic HS diet lead to impaired autoregulation in the cerebral circulation, with salt-induced ANG II suppression as a major factor in the initiation of impaired CBF regulation.

Source: Microcirculation

DOI: 10.1111/micc.12518

Authors: Linda A. Allen, James R. Schmidt, Christopher T. Thompson, Brian E. Carlson, Daniel A. Beard, Julian H. Lombard

Institutions: Medical College of Wisconsin, University of Michigan

Language: English

Topic: Renin-Angiotensin System Studies

Subfield: Cardiology and Cardiovascular Medicine

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: bronze

Funders: National Institutes of Health, National Heart, Lung, and Blood Institute, National Institute of General Medical Sciences