Intracellular reorganization and ultrastructural stereological analysis of cardiomyocytes of W/SSM rats with genetically determined cardiomyopathy

Abstract

We studied ultrastructure of cardiomyocytes of W/SSM rats with inherited hypertrophic cardiomyopathy bred from Wistar rats by hypersensitivity to cataractogenic action of high galactose doses. The observed dynamics of quantitative and qualitative changes in the main sarcoplasmic organelles reflects general principles of spatial and temporal reorganization of cardiac muscle cells induced by hypertrophy of different genesis.Key Words: W/SSM rats; hypertrophic cardiomyopathy; cardiomyocytes; electron microscopy; morphometry; stereology W/SSM rats with inherited hypertrophic cardiomyopathy were bred from Wistar rats selected by hypersensitivity to cataractogenic action of high galactose doses at the Institute of Cytology and Genetics, Siberian Division of the Russian Academy of Science [8,12,13]. These animals are characterized by spontaneous myocardium hypertrophy accompanied by diffuse stroma collagenization, focal sclerotic changes, and chronic cardiac insufficiency [6,7,9].One of the mechanisms of pathologic process is based on changes in plasma membrane integrity resulting from enhanced hexose transport into the cells, generation of free hydroxyradicals, and intensification of lipid peroxidation [ 1,17]. In the myocardium of W/ SSM rats with genetically determined disturbances of the carbohydrate metabolism and increased lysosome Thus, hypertrophic changes in the myocardium of W/SSM rats are similar to those observed during idiopathic human hypertrophic cardiomyopathy in the absence of anatomic or physiologic causes [11].The aim of the present study was to reveal intracellular changes in CMC and to determine ultrastructural stereological parameters typical of W/SSM rats with genetically determined hypertrophic cardiomyopathy. MATERIALS AND METHODSForty male W/SSM rats aged 3 and 10 months and 20 -male Wistar rats of the same age kept under standard vivarium conditions were used in the experiment. The animals were weighed and decapitated under chloro-

Structural Reorganization of the Adrenal Cortex in OXYS Rats during Ontogeny

“…Among these latter ones are SAM mice (more than 10 substrains are known) [11][12][13] and OXYS rats, bred in Russia, which are characterized by genetically determined metabolic defects [9]. Recent studies revealed shortening (by 28%) of the maximum life span in these animals, high incidence of "diseases of elderly age", early emergence of involution changes in the viscera, and cognitive deviations [1,[4][5][6][7][8].Study of the compensatory adaptive reactions and spatial reorganization of the adrenals is important, as adequate functioning of the adrenals maintains the regulation and interactions of many systems responsible for vital activity [10]. Despite the significance of age-specific reorganization of the adrenals and their individual structural and functional compartments, this aspect remains little studied.…”

“…Among these latter ones are SAM mice (more than 10 substrains are known) [11][12][13] and OXYS rats, bred in Russia, which are characterized by genetically determined metabolic defects [9]. Recent studies revealed shortening (by 28%) of the maximum life span in these animals, high incidence of "diseases of elderly age", early emergence of involution changes in the viscera, and cognitive deviations [1,[4][5][6][7][8].…”