Ballard K W, Paulsen G, Oren-Wolman N, Guth P H
Microvasc Res. 1983 Mar;25(2):176-85. doi: 10.1016/0026-2862(83)90013-4.
The purpose of this study was to determine whether alterations in the reactivity of gastric submucosal arterioles to norepinephrine and changes in acid secretion occur in the same time period in the rat. Experiments were performed on animals 6 weeks and 10, 18, and 25 months of age. Arteriolar diameter was measured by an image splitting in vivo microscopy technique before and after superfusion of the gastric submucosa with graded doses of norepinephrine. Acid secretion was measured in the pylorus-ligated rat. The percentage of arteriolar media stained with periodic acid-Schiff reagent (an age-related change) was determined for each age group. A dose-dependent response to norepinephrine was observed in 6-week and 10-, 18-, and 25-month age groups. Only in the 25-month-old rats were arterioles significantly more responsive to norepinephrine. Acid secretion at 10, 18, and 25 months was significantly less (about one-quarter) than that observed in the 6-week-old animals. Periodic acid-Schiff positive material deposited in the arteriolar media was significantly greater in the 18- and 25-month-old rats than in younger animals. We conclude that by 10 months of age in the rat, acid secretion is markedly reduced. The reactivity of the gastric submucosal arterioles is significantly increased at 25 months, but in the 18-month-old animal, when increased periodic acid-Schiff deposits are clearly evident, the reactivity to norepinephrine is not different from the 6-week-old rat.
本研究的目的是确定大鼠胃黏膜下小动脉对去甲肾上腺素反应性的改变以及胃酸分泌的变化是否在同一时期发生。对6周龄以及10、18和25月龄的动物进行了实验。在向胃黏膜下灌注不同剂量的去甲肾上腺素前后，采用图像分割体内显微镜技术测量小动脉直径。在幽门结扎的大鼠中测量胃酸分泌。测定每个年龄组用高碘酸-希夫试剂染色的小动脉中膜的百分比（一种与年龄相关的变化）。在6周龄以及10、18和25月龄的年龄组中观察到对去甲肾上腺素的剂量依赖性反应。仅在25月龄的大鼠中，小动脉对去甲肾上腺素的反应明显更强。10、18和25月龄时的胃酸分泌明显少于6周龄动物（约为四分之一）。在18和25月龄的大鼠中，沉积在小动脉中膜的高碘酸-希夫阳性物质明显多于年幼动物。我们得出结论，在大鼠10月龄时，胃酸分泌显著减少。胃黏膜下小动脉的反应性在25月龄时显著增加，但在18月龄的动物中，当高碘酸-希夫沉积物明显增加时，其对去甲肾上腺素的反应性与6周龄大鼠无异。
