Structural organization of the carotid sinus under the influence of monosodium glutamate in the experiment: analysis of changes in dynamics

Abstract

Carotid artery pathology is one of the leading causes of cerebral stroke. Among the pathogenetic factors in the development of carotid artery damage, disorders of lipid metabolism, atherosclerosis, and metabolic syndrome occupy a prominent place. The alimentary factor is extremely important in this context. Monosodium glutamate is one of the most common food additives, which is often used uncontrollably and can cause changes in the structure and functions of organs and tissues. The purpose of the study: to analyze the dynamics of morphological changes in the carotid sinus area under the influence of monosodium glutamate when administered orally in an experiment. The area of the carotid sinus of 20 male laboratory white rats that received sodium glutamate orally at a dose of 10 mg/kg/day for 8 weeks was studied by morphological methods at the macro- and microstructural levels after 6 and 8 weeks of the experiment. The obtained data are compared with the results of a morphological study of the same area in 20 animals of the control group. Statistical processing of animal weight was performed using MS Excel 2007 software. Mean ± standard deviation was determined. After 6 weeks of the experiment, when evaluating the histological structure of the wall of the internal carotid artery in the area located directly above the bifurcation, when compared with the control group, multiplication and folding of the intima were found in the experimental group, presumably associated with the proliferation of endothelial cells under the influence of sodium glutamate, detachment of the endothelium and lysis of individual endotheliocytes, as well as uneven thickening of elastic media fibers and disruption of their structure. Attention was drawn to the accumulation of white fat perivasally and in the zone of the carotid glomus, as well as the disorganization of nerves and the expansion of vessels of the microcirculatory channel. After 8 weeks of the experiment, the negative dynamics of structural changes were noticeable: signs of increased inflammatory infiltration, deformation of the vessels of the microcirculatory bed with thickening of their walls and narrowing of the lumen, stasis, noticeable degranulation of cells of type I carotid glomus cells, the appearance of single labrocytes (mast cells) in the infiltrate. The amount of adipose tissue (white fat) in the area of the carotid sinus and the perivasal bifurcation of the carotid arteries, as well as in the immediate vicinity of the carotid glomus, also increased markedly, and a tendency towards thickening of adipose tissue was noted. Thus, monosodium glutamate with systematic oral use can cause a violation of the structural organization of the carotid sinus, the wall of the carotid arteries and the carotid glomus, and the severity of changes in dynamics increases. Further research is needed to clarify the nature of the structural changes in the carotid sinus under the conditions of withdrawal of monosodium glutamate, as well as to find possible ways of correction.