NEUROTENSIN STIMULATES GROWTH OF COLONIC MUCOSA IN YOUNG AND AGED RATS
NEUROTENSIN STIMULATES GROWTH OF COLONIC MUCOSA IN YOUNG AND AGED RATS
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DOI：
10.1016/0016-5085(92)91099-p
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发表时间：
1992-07-01
期刊：
影响因子：
29.4
通讯作者：
THOMPSON, JC
中科院分区：
文献类型：
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作者：
EVERS, BM;IZUKURA, M;THOMPSON, JC
神经紧张素是一种广泛分布于肠道的三肽，可刺激幼龄和老年大鼠小肠黏膜的生长。本研究以幼龄大鼠（2月龄）和老龄大鼠（24月龄）为研究对象，观察了长期给药神经紧张素对结肠黏膜生长的影响。各组大鼠每8 h皮下注射生理盐水（对照组）或明胶中的神经紧张素（300 μg/kg），连续10 d。在治疗期间，所有大鼠都保持正常的饮食。第11天处死大鼠；切除整个结肠，刮取粘膜并称重，测定DNA、RNA和蛋白质含量。神经紧张素诱导两组结肠黏膜生长。在幼龄大鼠中，神经紧张素增加了体重和结肠粘膜的DNA、RNA和蛋白质含量。与年龄匹配的对照组相比，神经紧张素处理的幼鼠的DNA含量比率（细胞增生的指标）显著增加，表明粘膜细胞的总体增加。在老年大鼠中，生长的特征是体重增加，RNA和蛋白质含量增加，但DNA含量没有增加，这表明细胞肥大。提示神经紧张素对结肠黏膜的生长具有重要的调节作用；然而，作用方式，在细胞水平上，似乎是不同的取决于年龄。
Neurotensin, a tridecapeptide widely distributed in the gut, stimulates growth of small bowel mucosa in young and aged rats. In the present study, the effect of long-term neurotensin administration on the growth of colonic mucosa was examined in young (2-month-old) and aged (24-month-old) rats. Subcutaneous injections of saline (control) or neurotensin (300 μg/kg) in gelatin were given to the groups of rats every 8 hours for 10 days. During treatment, all rats were maintained on a regular chow diet. Rats were killed on day 11; the entire colon was removed, mucosa was scraped and weighed, and DNA, RNA, and protein contents were determined. Neurotensin induced growth of colonic mucosa in both age groups. In young rats, neurotensin increased weight and DNA, RNA, and protein contents of colonic mucosa. The ratio of DNA content, an index of cellular hyperplasia, was increased significantly in the neurotensin-treated young rats compared with age-matched controls, indicating an overall increase in mucosal cellularity. In the aged rats, growth was characterized by an increase in weight and RNA and protein contents, but not DNA content, thus suggesting cellular hypertrophy. These results suggest that neurotensin has an important regulatory function in the growth of colonic mucosa; however, the mode of action, at the cellular level, appears to be different depending on age.