Morphology of carotid sinus wall under the influence of monosodium glutamate and following its withdrawal: an experimental study

Abstract

The aim of this experimental study was to evaluate micro- and ultrastructural changes of the carotid sinus wall during oral consumption of low doses of monosodium glutamate (MG) and following its withdrawal. Adult male albino rats (n=39) were enrolled into the study. Carotid sinus wall morphology was assessed by light and electron microscopy at the end of week 4 and week 8 of MG oral consumption, as well as 2 weeks after its withdrawal; the results were compared with the control group. After 8 weeks of MG consumption, the wall of the carotid sinus was disorganized, endothelial layer of intima deformed, often without clear margins, the media edematous and dissected with thickened elastic membranes, and the cells of the vascular wall were showing signs of apoptosis while extra fat was present in the adventitia. Upon discontinuation of MG after 4 weeks of its consumption, the structural organization of carotid sinus wall was partially preserved, whereas no compensatory processes were registered after 8 weeks of MG administration followed by 2 weeklong withdrawal. Therefore, 8-week-long lowdose MG consumption resulted in pronounced changes of the micro- and ultra-structure of the carotid sinus wall of albino rats. Discontinuation of MG following 4 weeks of its administration partially improved the morphologic characteristics of the carotid sinus wall within 2 weeks. Withdrawal of MG after 8 weeks of its administration did not result in any improvement of the micro- and ultra- structure