AN EVALUATION OF THE IMPORTANCE OF GASTRIC-ACID SECRETION IN THE ADSORPTION OF DIETARY CALCIUM
AN EVALUATION OF THE IMPORTANCE OF GASTRIC-ACID SECRETION IN THE ADSORPTION OF DIETARY CALCIUM
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DOI：
10.1172/jci111254
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发表时间：
1984-01-01
影响因子：
15.9
通讯作者：
FORDTRAN, JS
中科院分区：
文献类型：
--
作者：
BOLINN, GW;DAVIS, GR;FORDTRAN, JS
由于钙的溶解度是钙吸收的先决条件，而且钙的溶解度高度依赖于pH，因此一般认为胃酸分泌和胃酸度在从摄入的食物或钙盐(如CaCO3)中吸收钙的过程中起着重要作用。为了评估这一假设，使用了一种方法，即在摄取一顿饭后，可以测量胃肠对钙的净吸收。大剂量西咪替丁可显著减少胃酸分泌，但对正常人及1例恶性贫血患者的钙吸收无明显影响。无论膳食中钙的主要来源是什么(即牛奶、不溶性碳酸钙或可溶性柠檬酸钙)，情况都是如此。当胃内含量维持在pH 7.4(体内滴定)时，摄入CaCO3后的CA吸收与胃内pH为3.0时相同。胃酸分泌和胃酸在正常情况下对膳食钙的吸收不起作用。本文还讨论了胃肠道溶解摄入的钙复合体和盐类的其他可能机制。
Since Ca solubility is a prerequisite to Ca absorption and since solubility of Ca is highly pH-dependent, it has been generally assumed that gastric acid secretion and gastric acidity play an important role in the intestinal absorption of Ca from ingested food or Ca salts such as CaCO3. To evalute this hypothesis, a method wherein net gastrointestinal absorption of Ca can be measured after ingestion of a single meal was used. A large dose of cimetidine, which markedly reduced gastric acid secretion, had no effect on Ca absorption in normal subjects and an achlorhydric patient with pernicious anemia absorbed Ca normally. This was true regardless of the major source of dietary Ca (i.e., milk, insoluble Ca carbonate or soluble Ca citrate). Ca absorption after CaCO3 ingestion was the same when intragastric contents were maintained at pH 7.4 (by in vivo titration) as when intragastric pH was 3.0. Gastric acid secretion and gastric acidity apparently do not normally play a role in the absorption of dietary Ca. Other possible mechanisms by which the gastriointestinal tract might solubilize ingested Ca complexes and salts are discussed.