运动期间饮料渗透压对肠液吸收的影响。

Effect of beverage osmolality on intestinal fluid absorption during exercise.

作者信息

Gisolfi C V, Summers R W, Lambert G P, Xia T

机构信息

Departments of Exercise Science and Internal Medicine, University of Iowa, Iowa City, Iowa 52242-1111, USA.

出版信息

J Appl Physiol (1985). 1998 Nov;85(5):1941-8. doi: 10.1152/jappl.1998.85.5.1941.

DOI:10.1152/jappl.1998.85.5.1941

PMID:9804602

Abstract

To determine how osmolality of an orally ingested fluid-replacement beverage would alter intestinal fluid absorption from the duodenum and/or jejunum during 85 min of cycle exercise (63.3 +/- 0.9% peak O2 uptake) in a cool environment (22 degreesC), seven subjects (5 men, 2 women, peak O2 uptake = 54.5 +/- 3.8 ml . kg-1 . min-1) participated in four experiments separated by 1 wk in which they ingested a water placebo (WP) or one of three 6% carbohydrate (CHO) beverages formulated to give mean osmolalities of 197, 295, or 414 mosmol/kgH2O. CHO solutions also contained 17-18 meq Na+ and 3.2 meq K+. Nasogastric and multilumen tubes were fluoroscopically positioned in the gastric antrum and duodenojejunum, respectively. Subjects ingested a total of 23 ml/kg body mass of the test solution, 20% (370 +/- 9 ml) of this volume 5 min before exercise and 10% (185 +/- 4 ml) every 10 min thereafter. By using the rate of gastric emptying as the rate of intestinal perfusion (G. P. Lambert, R. T. Chang, D. Joensen, X. Shi, R. W. Summers, H. P. Schedl, and C. V. Gisolfi. Int. J. Sports Med. 17: 48-55, 1996), intestinal absorption was determined by segmental perfusion from the duodenum (0-25 cm) and jejunum (25-50 cm). There were no differences (P > 0.05) in gastric emptying (mean 18.1 +/- 1.3 ml/min) or total fluid absorption (802 +/- 109, 650 +/- 52, 674 +/- 62, and 633 +/- 74 ml . 50 cm-1 . h-1 for WP, hypo-, iso-, and hypertonic solutions, respectively) among beverages; but WP was absorbed faster (P < 0.05) from the duodenum than in the jejunum. Of the total volume of fluid ingested, 82 +/- 14, 74 +/- 6, 76 +/- 5, and 68 +/- 7% were absorbed for WP, hypo-, iso-, and hypertonic beverages, respectively. There were no differences in urine production or percent change in plasma volume among solutions. We conclude that total fluid absorption of 6% CHO-electrolyte beverages from the duodenojejunum during exercise, within the osmotic range studied, is not different from WP.

摘要

为了确定在凉爽环境（22摄氏度）下进行85分钟的周期性运动（达到峰值摄氧量的63.3±0.9%）期间，口服补液饮料的渗透压如何改变十二指肠和/或空肠的肠液吸收，七名受试者（5名男性，2名女性，峰值摄氧量=54.5±3.8毫升·千克⁻¹·分钟⁻¹）参与了四项实验，实验间隔为1周，期间他们分别摄入水安慰剂（WP）或三种6%碳水化合物（CHO）饮料之一，这三种饮料的平均渗透压分别为197、295或414毫摩尔/千克H₂O。CHO溶液还含有17 - 18毫当量的Na⁺和3.2毫当量的K⁺。通过荧光镜检查将鼻胃管和多腔管分别置于胃窦和十二指肠空肠处。受试者总共摄入23毫升/千克体重的测试溶液，其中20%（370±9毫升）在运动前5分钟摄入，之后每10分钟摄入10%（185±4毫升）。通过将胃排空速率作为肠灌注速率（G.P. Lambert、R.T. Chang、D. Joensen、X. Shi、R.W. Summers、H.P. Schedl和C.V. Gisolfi。《国际运动医学杂志》17: 48 - 55，1996），通过十二指肠（0 - 25厘米）和空肠（25 - 50厘米）的分段灌注来测定肠吸收。各饮料之间在胃排空（平均18.1±1.3毫升/分钟）或总液体吸收方面无差异（P>0.05）（WP、低渗、等渗和高渗溶液的总液体吸收分别为802±109、650±52、674±62和633±74毫升·50厘米⁻¹·小时⁻¹）；但WP从十二指肠的吸收比在空肠更快（P<0.05）。在摄入的总液体量中，WP、低渗、等渗和高渗饮料分别有82±14%、74±6%、76±5%和68±7%被吸收。各溶液之间在尿量产生或血浆容量百分比变化方面无差异。我们得出结论，在运动期间，在所研究的渗透压范围内，6% CHO - 电解质饮料从十二指肠空肠的总液体吸收与WP没有差异。