Poston G J, Saydjari R, Lawrence J P, Chung D, Townsend C M, Thompson J C
Department of Surgery, University of Texas Medical Branch, Galveston 77550.
Pancreas. 1991 Jul;6(4):407-11. doi: 10.1097/00006676-199107000-00006.
We examined the effect of age on the trophic response of the pancreas to chronic treatment with cholecystokinin (CCK), bombesin, or pentagastrin. Three age groups (3-, 12-, and 24-months) male F344 rats received saline; CCK-8 (5 ng/kg), bombesin (10 micrograms/kg), or pentagastrin (100 micrograms/kg) by intraperitoneal injection t.i.d. for 2 weeks. Rats were then killed and the pancreases excised, weighed, and assayed for DNA, RNA, protein, and polyamine (putrescine, spermidine, and spermine) concentrations and contents. We found that none of the treatments altered body weight at any age. All three hormones increased pancreas size and cell number in 3-month old rats, but by 12 months, all three had increased only pancreatic RNA content. Pancreatic spermidine concentration was decreased by all three hormone regimens in 3- but not in 12-month old rats, and pancreatic putrescine concentration and content were increased in 12-month old rats receiving all three hormones. There was no change in any parameter following any of the three hormones, tested at 24 months of age. We conclude that, at the dosages tested, the trophic response of pancreas to chronic administration of CCK, bombesin, and pentagastrin, which is normally present in young adult rats, is lost with aging.
我们研究了年龄对胰腺经胆囊收缩素（CCK）、蛙皮素或五肽胃泌素长期治疗后的营养反应的影响。三个年龄组（3个月、12个月和24个月）的雄性F344大鼠接受生理盐水；或通过腹腔注射，每日三次，连续2周给予CCK-8（5纳克/千克）、蛙皮素（10微克/千克）或五肽胃泌素（100微克/千克）。然后处死大鼠，切除胰腺，称重，并检测DNA、RNA、蛋白质以及多胺（腐胺、亚精胺和精胺）的浓度和含量。我们发现，在任何年龄，所有处理均未改变体重。在3个月大的大鼠中，所有三种激素均增加了胰腺大小和细胞数量，但到12个月时，所有三种激素仅增加了胰腺RNA含量。在3个月大的大鼠中，所有三种激素处理方案均降低了胰腺亚精胺浓度，但在12个月大的大鼠中未降低；在接受所有三种激素的12个月大的大鼠中，胰腺腐胺浓度和含量增加。在24个月大时，对任何一种激素进行测试后，任何参数均无变化。我们得出结论，在所测试的剂量下，胰腺对CCK、蛙皮素和五肽胃泌素慢性给药的营养反应（这在年轻成年大鼠中通常存在）会随着衰老而丧失。
