Pathogenetic features of the nitric oxide system state in the left ventricular myocardium of the rats with experimental arterial hypertension

Isachenko M. I., Melnikova O. V. Pathogenetic features of the nitric oxide system state in the left ventricular myocardium of the rats with experimental arterial hypertension. Journal of Education, Health and Sport. 2020;10(8):476-489. eISSN 2391-8306. DOI http://dx.doi.org/10.12775/JEHS.2020.10.08.058 https://apcz.umk.pl/czasopisma/index.php/JEHS/article/view/JEHS.2020.10.08.058 https://zenodo.org/record/4017794 The journal has had 5 points in Ministry of Science and Higher Education parametric evaluation. § 8. 2) and § 12. 1. 2) 22.02.2019. © The Authors 2020; This article is published with open access at Licensee Open Journal Systems of Nicolaus Copernicus University in Torun, Poland Open Access. This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author (s) and source are credited. This is an open access article licensed under the terms of the Creative Commons Attribution Non commercial license Share alike. (http://creativecommons.org/licenses/by-nc-sa/4.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited. The authors declare that there is no conflict of interests regarding the publication of this paper. Received: 04.08.2020. Revised: 14.08.2020. Accepted: 31.08.2020. UDC: 616.124:616.12-008.331.1]-092.9 PATHOGENETIC FEATURES OF THE NITRIC OXIDE SYSTEM STATE IN THE LEFT VENTRICULAR MYOCARDIUM OF THE RATS WITH EXPERIMENTAL ARTERIAL HYPERTENSION M. I. Isachenko, O. V. Melnikova Zaporizhzhia State Medical University, Ukraine Department of Pathological Physiology Isachenko M. I., Post-graduate student of the Department of Pathophysiology, Zaporizhzhia State Medical University, Zaporizhzhia, Ukraine. fedotova@zsmu.pp.ua +380973029038 ORCID ID: 0000-0002-3026-1012. Melnikova O. V., MD, PhD, Associate Professor of the Department of Pathophysiology, Zaporizhzhia State Medical University, Ukraine. ORCID: 0000-0002-6807-8440 Abstract The aim was to determine the pathogenetic features of the NO system in the myocardium of the left ventricle in the rats with endocrine-salt hypertension. Material and methods. The experiment was conducted on 20 male rats 220-290 g weight, 6–10 months old which were divided into 2 experimental groups: 1st – the control group (10 intact normotensive male Wistar rats); 2nd – 10 male Wistar rats with endocrine-salt arterial hypertension. Systolic and diastolic BP levels were measured in all the rats using a system of non-invasive arterial pressure measurement BP-2000. The objects of study in the experimental animals were blood plasma in which the nitrotyrosine level was measured, and the fragment of left ventricle, which was divided into two parts, one of which was homogenized using a Silent Crusher S homogenizer (Heidolph, Germany), in which nitrites level was determined. Concentration of immunoreactive material to NOS isoforms was detected with immunofluorescence method. The study of NOS mRNA isoforms expression in the left ventricular myocardium homogenates was carried out using a real-time polymerase chain reaction Results. In the experiment, an increase in all 3 isoforms and their mRNA was obtained. In the study, a decrease in nitrites concentration and a significant increase in nitrotyrosine levels, indicates the development of nitroso-oxidative stress. Conclusions. The development of experimental endocrine-salt hypertension in the Wistar rats leads to a stable increase in mean blood pressure by 65% compared to control. Endocrine-salt arterial hypertension in Wistar rats is characterized by an increased mRNA content of all three isoforms of nNOS, eNOS and iNOS by 2.7, 2.8 and 5.7 times, respectively, compared to the control; increased expression of immunoreactive material to isoforms in transverse fibers by 14.3%, 16.2% and 18.5%, respectively; in longitudinal fibers IRM to nNOS was higher by 8.3%, to iNOS - by 8.5%, but to eNOS it was lower by 7.6%. At the same time, nitrites level decreased by 11.7% and nitrotyrosine concentration was significantly higher, exceeding the control value by 88.5%. Key words: nitric oxide synthase; NOS isoforms; myocardium; left ventricle; heart; Wistar rats; endocrine-salt arterial hypertension; secondary hypertension.