探讨比格犬胃窦黏膜组织学与超微结构的增龄变化特点。

选取健康比格犬(犬龄1.5～11.0岁，体重14～20 kg)19只。按年龄分组：≥1.5岁且≤6岁8只(中青年组)，>6岁且≤9岁5只(低龄老年组)，>9岁且≤11岁6只(高龄老年组)。光镜下观察对比各组犬胃窦黏膜上皮细胞形态学变化、胃窦黏膜炎症程度、肠上皮化生和异型增生情况、固有膜厚度及黏液腺体实质比的变化；透射电镜下观察对比各组犬胃窦黏膜上皮细胞形态、细胞间连接、幽门腺细胞黏原颗粒面积分数的变化。3组间胃黏膜炎症指数、胃窦黏膜固有膜厚度及黏液腺体实质比的比较采用单因素方差分析。

光镜观察结果：各组犬胃窦黏膜上皮细胞未见明显形态学变化；胃窦黏膜内均未见肠上皮化生、异型增生，且无炎症或炎症表现轻微，各组间炎症指数无明显差异(F＝0.023，P>0.05)；中青年组、低龄老年组及高龄老年组胃窦黏膜固有膜厚度分别为(1016.7±203.2)、(727.5±64.3)、(931.7±92.4) μm，差异有统计学意义(F＝5.952，P<0.05)，其中高龄老年组黏膜内结缔组织增生明显；3组黏液腺体实质比分别为(45.3±6.4)%、(33.9±2.4)%、(34.5±6.3)%，差异有统计学意义(F＝8.981，P<0.01)。透射电镜观察结果：各组胃窦黏膜上皮细胞超微结构及细胞间紧密连接均未见明显改变，但细胞间中间连接及缝隙连接随增龄逐渐疏松，并可见空泡样缝隙；中青年组、低龄老年组及高龄老年组幽门腺细胞内黏原颗粒面积分数分别为(50.3±10.0)%、(44.4±3.9)%、(18.6±5.6)%，差异有统计学意义(F＝15.501，P<0.01)。

健康比格犬胃窦黏膜组织学和超微结构随增龄出现了一系列退化现象。

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.