摘要
目的观察卧床模拟失重所致血浆肾素活性(PRA)、醛固酮(Ald)及前列腺素(PGI2)的变化和LBNP对抗措施对上述激素的影响。方法12名健康男性志愿者进行了21dHDT-6°卧床实验。被试者年龄23.7±5.0岁,随机等分为对照组(CON)和下体负压(LBNP)组。LBNP组在卧床最后一周进行下体负压锻炼(-30mmHg,1h/d)。卧床前、卧床第2、4、11天及卧床结束日清晨分别抽取肘静脉血。结果与卧床前相比,Ald在第2天显著下降(CON-30%,P<0.05;LBNP-38%,P<0.01),在第11天显著上升(CON+30%,P<0.05;LBNP+48%,P<0.01)。PRA在第4天达到峰值(P<0.05),第22天回落到低于对照水平。PGI2在HDT过程中均高于对照水平。对照组在第22天增加+260%(P<0.01),LBNP组在第11天,第22天分别升高149%,102%(P<0.05)。采用LBNP对抗措施后,PRA,Ald在两组间无明显差别,PGI2在LBNP组未进一步升高。结论21d头低位卧床导致PRA、Ald的一过性升高及PGI2持续性升高。
Objective To investigate variations of plasma renin activity(PRA),aldosterone (Ald) and prostaglandin I 2 (PGI 2) during 21d -6° head down tilt (HDT) with and without lower body negative pressure (LBNP). Method -6°head down tilt for 21d were used to simulate weightlessness.12 healthy male, aged 23.7±5.0, were equally and randomly divided into control group (CON) and LBNP group.The latter subjected to LBNP (-30mm Hg,1h/d) in the last week of HDT. Samples of plasma were taken before HDT and on the 2nd,4th,11th and 22nd day during HDT. Result Compare to control levels, Ald declined significantly on the 2nd (CON -30%,P<0.05;V.S.LBNP -38%,P<0.01),and increased significantly on the 11th day(CON +30%,P<0.05;LBNP +48%,P<0.01).PRA reached peak value on the 4th day(P<0.05),and declined to below the control level on the 22nd day.PGI 2 increased constantly during HDT,and increased significantly on the 22nd day (CON P< 0.01 ),11th,22nd (LBNP P<0.05). No apparent difference was found between groups after LBNP concerning PRA and Ald;and PGI 2 didn't increase further in LBNP group. Conclusion HDT induced a timely increasing in PRA and Ald , constant increasing in PGI 2.
出处
《航天医学与医学工程》
CAS
CSCD
1999年第4期258-261,共4页
Space Medicine & Medical Engineering
基金
863资助项目
关键词
下体负压
前列腺素类
肾素
血管紧张素
模拟失重
lower body negative pressure
prostaglandins
renin angiotensin aldosterone system
simulated weightlessness
bed rest tests.