Circadian Variation in Vasoconstriction and Vasodilation Mediators and Baroreflex Sensitivity in Hypertensive Rats.

Autor: Kezeli T; Department of Pharmacology, Faculty of Medicine, I. Javakhishvili Tbilisi State University, Tbilisi, GE., Gongadze N; Department of Medical Pharmacology, Tbilisi State Medical University, Tbilisi, GE., Sukoyan G; Department of Molecular and Clinical Pharmacology, International Scientific Centre of Introduction of New Biomedical Technology, Tbilisi, GE., Shikhashvili M; Department of Pharmacology, Faculty of Medicine, I. Javakhishvili Tbilisi State University, Tbilisi, GE., Chapichadze Z; David Tvildiani Medical University, Tbilisi, GE., Okujava M; Department of Pharmacology, Faculty of Medicine, I. Javakhishvili Tbilisi State University, Tbilisi, GE., Dolidze N; State Regulation Agency for Medical Activities, Tbilisi, GE.
Jazyk: angličtina
Zdroj: Journal of circadian rhythms [J Circadian Rhythms] 2019 Oct 14; Vol. 17, pp. 10. Date of Electronic Publication: 2019 Oct 14.
DOI: 10.5334/jcr.185
Abstrakt: The purpose of this study was to evaluate the relationship between the circadian profile of the vasorelaxing substances calcitonin gene-related peptide (CGRP) and epoxyeicosatrienoic acids (EETs) and the vasconstrictive agent endothelin-1 (ET1) and the daily rhythms of cardiac hemodynamic indices (CHI) and baroreflex (BRS) in Wistar rats with 1 kidney-1 clip model of arterial hypertension (1K-1C AH). The animals were divided into 3 groups: I- sham-operated (SO), II- 4-week and III- 8-week 1K-1C AH rats. Plasma concentration of ET1, CGRP and EET's were investigated every 4 h. In conscious freely moving 1K-1C AH rats unlike SO animals blood pressure (BP), heart period (HP) and BRS underwent significant circadian fluctuations, with more marked increase in mean values of BP in 8-week hypertensive rats in comparison to 4-week hypertensive rats (179 ± 5 vs. 162 ± 4 mm Hg, p < 0.05). These alterations correlated with more significant reduction in HP (138 ± 5 vs. 150 ± 6 ms, p < 0,05) and BRS (0.44 ± 0.04 vs. 0.58 ± 0.04 ms mm Hg -1 , p < 0.05) in 8-week 1K-1C AH rats. The acrophases of BP in 8-week 1K-1C AH rats in comparison with 4-week were shifted to more late night hours (1:58 a.m. vs. 11:32 p.m.) and in both groups of animals corresponded to lowest circadian plasma levels of CGRP and EETs and to greatest level of ET1. SO rats were characterized by lower values of BP (121 ± 3 mm Hg, p < 0,05) and higher indices of HP (158 ± 2 ms, p < 0,05) and BRS (0.86 ± 0.02 ms mmHg -1 , p < 0,001) in comparison with 1K-1C AH rats 4-week duration. The acrophases of BP, HP and BRS in hypertensive animals were revealed at 14.8 ± 0.5 h, 13.6 ± 0.4 h and 13.1 ± 0.2 h, which correlated with maximal circadian contents of ET1 and CGRP at 24:00 h and EETs at 12:00 h and were shifted in comparison to sham-operated group. In rats with 1K-1C AH, plasma levels of ET1, CGRP and EETs undergo circadian fluctuation with corresponding alterations in CHI and BRS which are more markedly expressed on the late stage of diseases and could be used in future for predictive, preventive, and personalized treatment of arterial hypertension.
Competing Interests: The authors have no competing interests to declare.
(Copyright: © 2019 The Author(s).)
Databáze: MEDLINE
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