Tikhomirova I A
Department of Anatomy and Physiology, Pedagogical State University, Yaroslavl, Russia.
Clin Hemorheol Microcirc. 2002;26(2):85-90.
It is known that intensive physical activity causes a loss of water. Since physical capacity is highly dependent upon fluidity of blood, the rheological characteristics of which are largely determined by water content, the aim of our study was to estimate rheological properties of blood under dehydration. To model the state of dehydration, the water deprivation was performed on rats (n=49) for 3 and 10 days. We registered hematocrit, apparent plasma viscosity; apparent viscosity, rigidity index (Tk), structural parameter (k), and extent of aggregation ("M" and "M1" indices) were determined in both unfractionated and density separated RBC suspensions in autologous plasma at Ht=40. The Ht/viscosity ratio as index of oxygen supply to tissues was calculated. The results of our study indicated that water deprivation caused progressive reduction of blood and plasma fluidity. The increase of Ht (22%, p<0.001) and significant elevation of erythrocyte aggregation (205%, p<0.001) were observed. In spite of Ht increase, oxygen transport was decreased by 18% (p<0.05). RBC rigidity was increased under water deprivation (13.6%, p<0.05) as well as during aging. Significant correlation was found between indices of aggregation and Tk and k indices in the course of dehydration. Thus, our data indicated that dehydration caused impairment of blood and RBC rheological properties.
众所周知，高强度体育活动会导致水分流失。由于身体机能高度依赖血液的流动性，而血液的流变学特性很大程度上由含水量决定，因此我们研究的目的是评估脱水状态下血液的流变学特性。为模拟脱水状态，对49只大鼠进行了3天和10天的禁水实验。我们记录了血细胞比容、表观血浆粘度；在血细胞比容为40%的自体血浆中，对未分级和密度分离的红细胞悬液测定了表观粘度、刚性指数（Tk）、结构参数（k）以及聚集程度（“M”和“M1”指数）。计算了作为组织氧供应指标的血细胞比容/粘度比值。我们的研究结果表明，禁水导致血液和血浆流动性逐渐降低。观察到血细胞比容增加（22%，p<0.001）以及红细胞聚集显著升高（205%，p<0.001）。尽管血细胞比容增加，但氧运输减少了18%（p<0.05）。禁水期间以及衰老过程中红细胞刚性均增加（13.6%，p<0.05）。在脱水过程中，聚集指数与Tk和k指数之间存在显著相关性。因此，我们的数据表明脱水导致血液和红细胞流变学特性受损。
