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.
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.
Authors: Irene Rozet; Monica S Vavilala; Andrew M Lindley; Elizabeth Visco; Miriam Treggiari; Arthur M Lam Journal: Anesth Analg Date: 2006-02 Impact factor: 5.108
Authors: Ana Cavka; Anita Cosic; Ivana Jukic; Bojan Jelakovic; Julian H Lombard; Shane A Phillips; Vatroslav Seric; Ivan Mihaljevic; Ines Drenjancevic Journal: J Physiol Date: 2015-12-07 Impact factor: 5.182
Authors: Jody L Greaney; Jennifer J DuPont; Shannon L Lennon-Edwards; Paul W Sanders; David G Edwards; William B Farquhar Journal: J Physiol Date: 2012-08-20 Impact factor: 5.182
Authors: Rogier V Immink; Bert-Jan H van den Born; Gert A van Montfrans; Richard P Koopmans; John M Karemaker; Johannes J van Lieshout Journal: Circulation Date: 2004-10-04 Impact factor: 29.690
Authors: Wenjin Liu; Xiaoqin Huang; Xuebing Liu; Lulu Wang; Zhensen Chen; Dakota Ortega; Li Chen; Jie Sun; Thomas S Hatsukami; Chun Yuan; Haige Li; Junwei Yang Journal: Eur J Nutr Date: 2021-06-19 Impact factor: 5.614
Authors: Kamila U Migdal; Austin T Robinson; Joseph C Watso; Matthew C Babcock; Shannon L Lennon; Christopher R Martens; Jorge M Serrador; William B Farquhar Journal: Auton Neurosci Date: 2021-05-27 Impact factor: 2.355