Aging related changes in the gastric enteroendocrine cells

ABSTRACT

The aim of this study was to demonstrate the age-related histological changes in the gastric enteroendocrine [EN] cells. This study was conducted on 30 male albino rats divided into three groups. Each group comprised 10 animals aged 4, 12, 24 months. Paraffin sections were prepared from specimens of the gastric mucosa and stained by Hx and E, toluidine blue, Grimelius silver stains. Small tissue pieces were obtained from the gastric mucosa of young [4 month old] rats and senescent [24 month old] rats and used for electron microscopic study. Morphometric studies and statistical analysis of the obtained data were done. The gastric mucosa of young [4 month old] rats showed EN cells which were mostly found in the gland bases and appeared as small cells with clear cytoplasm and rounded nuclei and gave positive argyrophilic reaction. The gastric mucosa of old [12 month old] rats demonstrated an increase in the number of EN cells. The gastric mucosa of senescent [24 month old] rats showed changes similar to those of old rats with further increase in the number of EN cells especially in the dilated glands. Electron microscopic study of young rat gastric mucosa demonstrated three types of EN cells with different secretory granules. Electron microscopic study of senescent rat gastric mucosa demonstrated the EN cells with some changes in their cytoplasm and granules. Statistical results demonstrated a significant increase in the number and diameter of EN cells. It was concluded that aging is associated with an increase in the number and diameter of EN cells. The morphometric changes that occur in the gastric mucosal EN cells with age seem to be responsible for the gastric functional disorders observed in the elderly or could be secondary to structural and functional changes in the alimentary tract caused by aging