%0 Journal Article
%T Effect of salt intake on beat©\to©\beat blood pressure nonlinear dynamics and entropy in salt©\sensitive versus salt©\protected rats
%A Joseph R. Habib
%A Kamal F. Badr
%A Milo C. Engoren
%A Robert H. Habib
%A Souha A. Fares
%J Archive of "Physiological Reports".
%D 2016
%R 10.14814/phy2.12823
%X Blood pressure exhibits substantial short©\ and long©\term variability (BPV). We assessed the hypothesis that the complexity of beat©\to©\beat BPV will be differentially altered in salt©\sensitive hypertensive Dahl rats (SS) versus rats protected from salt©\induced hypertension (SSBN13) maintained on high©\salt versus low©\salt diet. Beat©\to©\beat systolic and diastolic BP series from nine SS and six SSBN13 rats (http://www.physionet.org) were analyzed following 9 weeks on low salt and repeated after 2 weeks on high salt. BP complexity was quantified by detrended fluctuation analysis (DFA), short©\ and long©\range scaling exponents (¦Á S and ¦Á L), sample entropy (SampEn), and traditional standard deviation (SD) and coefficient of variation (CV(%)). Mean systolic and diastolic BP increased on high©\salt diet (P < 0.01) particularly for SS rats. SD and CV(%) were similar across groups irrespective of diet. Salt©\sensitive and ©\protected rats exhibited similar complexity indices on low©\salt diet. On high salt, (1) SS rats showed increased scaling exponents or smoother, systolic (P = 0.007 [¦Á L]) and diastolic (P = 0.008 [¦Á L]) BP series; (2) salt©\protected rats showed lower SampEn (less complex) systolic and diastolic BP (P = 0.046); and (3) compared to protected SSBN13 rats, SS showed higher ¦Á L for systolic (P = 0.01) and diastolic (P = 0.005) BP. Hypertensive SS rats are more susceptible to high salt with a greater rise in mean BP and reduced complexity. Comparable mean pressures in sensitive and protective rats when on low©\salt diet coupled with similar BPV dynamics suggest a protective role of low©\salt intake in hypertensive rats. This effect likely reflects better coupling of biologic oscillators
%K Beat©\to©\beat variability
%K complexity
%K detrended fluctuation analysis
%U https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4908498/