45d-6°头低位卧床对尿Ca和P含量及其昼夜节律的影响  

Influence of 45 d-6° Head-down Bed Rest on Concentration and Circadian Rhythms of Urinal Calcium and Phosphorus

作　　者：万宇峰[1] 张琳[1] 喻昕阳 郭一鸣[1] 于嘉利 李泓萤 吴轶兰[1] 柯云[1] 王政[2] 肖毅[2] 谈诚[2] 田雨[2] 王春慧[2] 陈晓萍[2] 陈善广[2] 郭金虎[1] 

机构地区：[1]中山大学生命科学学院,广东广州510006 [2]中国航天员科研训练中心,北京100094

出　　处：《航天医学与医学工程》2015年第1期11-15,共5页Space Medicine & Medical Engineering

基　　金：国家重点基础研究计划973项目(2011CB711000;2012CB947603);国家自然科学基金面上项目(31171119);西北工业大学空间生物实验模拟技术国防重点学科实验室开放基金(2013KF1501);中国航天员中心人因工程重点实验室自主课题(HF2011ZZA01);总装实验技术课题(2012SY54B1701)

摘　　要：目的研究45 d-6°头低位卧床对尿液中Ca和P元素昼夜节律的影响,探讨卧床实验中骨丢失的可能规律与机制。方法收集卧床实验8名受试者尿样,每个时间段连续收集3 d。采用电感耦合等离子体发射光谱仪(ICP-OES)对尿样中的Ca,P和K三种元素的含量进行检测,并对Ca和P等元素的昼夜节律特征进行分析。结果尿Ca总含量在卧床前、中、后3个时间段无显著差异,但Ca元素的日间含量在卧床中的早期和晚期阶段都显著降低,在卧床后又恢复至接近卧床前水平。尿中P元素总含量在卧床中的早期显著升高,随后不断下降,到卧床晚期则显著低于卧床前水平,P元素在日间和夜间的变化趋势差异不大。反映骨质变化的Ca/P参数在卧床中和卧床后也有显著变化。此外,卧床实验也对尿液中Ca和P含量变化的昼夜节律具有影响。结论卧床实验对于尿中Ca和P含量及Ca/P参数产生显著影响,同时也影响了Ca和P含量的节律性,这些变化可能与卧床过程中骨代谢失衡有关。Objective To investigate the influence of 45 d-6° head-down bed rest（ HDBR） on the circadian rhythms of urinal calcium and phosphorus elements,as well as their correlation with the imbalance of bone metabolism and bone loss. Methods Urinal samples of 8 subjects were collected in pre-HDBR,HDBR,and postHDBR respectively for 3 consecutive days in each measurement block. The concentration of calcium（ Ca）,phosphorus（ P） and potassium（ K） elements was measured with Inductively Coupled Plasma Optical Emission Spectrometer（ ICP-OES）,and the circadian rhythms of Ca and P elements were analyzed. Results The total concentration of urinal Ca was not significantly changed throughout the bed rest. However,Ca level in the daytime was significantly decreased in both the early and late stages during HDBR,and after HDBR it was increased to the level before HDBR. The total level of urinal P was significantly increased in the early stage during HDBR,and decreased gradually afterwards,thus the level of P in the late period during HDBR was significantly lower than that before HDBR. The difference in P levels between daytime and nighttime was not significant. The values of Ca / P ratio were also changed significantly during and after HDBR. In addition,the impact of HDBR on the circadian rhythms of urinal Ca and P was observed. Conclusion HDBR imposes significant influences on the concentrations of urinal calcium and phosphorus and Ca / P ratio,as well as the circadian rhythms of calcium and phosphorus elements. These changes may contribute to the imbalance in bone metabolism and bone loss caused by HDBR.

关 键 词：头低位卧床 昼夜节律 钙 磷 骨代谢稳态 

分 类 号：R852[医药卫生—航空、航天与航海医学]