To observe the influence of aging on the degeneration morphological changes of antral mucosa.

Nineteen healthy Beagles were divided randomly into three groups: young group (≥1.5 years old and ≤6 years old, n=8), junior elderly group (>6 years old and ≤9 years old, n=5), senior elderly group (>9 years old and ≤11 years old, n=6). The antral mucosal histology was observed; semi-quantitative analysis of inflammatory index were calculated; the thickness of lamina propria was measured and the mucosal gland density was calculated. The ultra structure of antral mucosal epithelial cells and pyloric glandular cells were studied and as well as cell junctions by electron microscopy.

There was no intestinal metaplasia or dysplasia in any specimen. The morphology of epithelial cells and inflammation index of antral mucosal showed no significant changes among three groups. The thickness of lamina propria indicate no significant difference among young group (1016.7±203.2) μm, junior elderly group (727.5±64.3) μm, senior elderly group (931.7±92.4) μm (F=5.592, P<0.05). The proportion of mucosal glands decreased significantly with aging [(45.3±6.4) %, (33.9±2.4) %, (34.5±6.3) %, F=8.981, P<0.01]. The ultra structures of epithelial cells and tight junctions had no significant changes; while middle junctions and gap junctions had gradually loosen with aging. The area percentage of organelles which associated with mucus secretion, decreased significantly with aging [(50.3±10.0)%, (44.4±3.9)%, (18.6±5.6)%, F=15.501, P<0.01].

The results suggest that the morphology of Beagles antral mucosa deteriorate significantly.