The study on atrial natriuretic peptide of cardiomyocytes in a remote post-reperfusion period in experiment

UDC 57.086:612.018.591.8:61–089.5 Received 16.10.2013M.L. Bugrova, PhD, Associate Professor, Head of Electron Microscopy Unit, Central Scientific Research Laboratory of Scientific Research Institute of Applied and Fundamental Medicine;D.А. Abrosimov, Postgraduate, the Department of Histology with Cytology and Embryology;E.I. Yakovleva, PhD, Senior Research Worker, Electron Microscopy Unit, Central Scientific Research Laboratory of Scientific Research Institute of Applied and Fundamental Medicine;О.S. Baskina, PhD, Research Worker, the Morphology Department, Central Scientific Research Laboratory of Scientific Research Institute of Applied and Fundamental Medicine;I.L. Ermolin, D.Bio.Sc., Professor, Head of the Department of Histology with Cytology and EmbryologyNizhny Novgorod State Medical Academy, Minin and Pozharsky Square, 10/1, Nizhny Novgorod, Russian Federation, 603000The aim of the investigation was to assess the intensity of rat atrial natriuretic peptide (ANP) accumulation and release in a remote post-reperfusion period after a 10-minute circulatory arrest using quantitative analysis of secretory cardiomyocyte granules, morphological and physiological methods.Materials and Methods. The experiments were carried out on 19 non-linear male rats weighting 220–250 g. Total ischemia (10 min) was simulated by cardiovascular bundle compression according to V.G. Korpachev. The intensity of ANP accumulation and release processes was assessed by quantitative analysis of immunolabeled atrial myocyte granules in transmission electron microscope. We studied tissue rearrangement in myocardium at light-optical level. Physiological condition of animal was assesses in post-reperfusion period by heart rate variability and arterial pressure level.Results. Rat atrial myocytes in a remote post-reperfusion period were found to have intensified ANP accumulation and release processes. An increased release proceeds against the background of synthetic and proliferative activity of fibroblasts and has a cardioprotective effect promoting the decrease of cardiosclerosis development. Released ANP participates in cardiac rhythm recovery under elevated blood pressure.Conclusion. Quantitative analysis of immunolabeled granules together with a complex of morphological and physiological methods indicates the intensification of atrial natriuretic peptide accumulation and release in rat atrial cardiomyocytes by the 60