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When the body is in space flight, weightlessness or microgravity environment , hydrostatic pressure disappears , head to the distribution of body fluids , return to the ground 1G environment, will adversely affect the human cardiovascular system , cardiovascular disorders , mainly as orthostatic intolerance decline . Weightlessness or microgravity environment of the mechanism of cardiovascular dysfunction is complex, multifaceted, mainly the following reasons: decreased heart function , cardiac output when compared with pre-flight supine position reduced by 10 % to 20% ; weightlessness cause reflex polyuria , water and salt from the urine , so that hypovolemia ; decreased cerebral blood flow ; venous compliance increased and so on. Previously carried out by weightlessness or simulated weightlessness experiments show that reduced blood volume blood loss will cause similar changes in the cardiovascular system . In addition to the distribution of weight loss after fluid head , about 2000 ml of blood from the lower extremities transferred to the upper body , on cerebral blood flow will have a significant impact , causing cerebral blood flow velocity and pressure receptors regulate changes. These factors will directly affect blood pressure and blood flow changes . Therefore, the study weightlessness human blood pressure , changes in blood flow can study the mechanism of cardiovascular dysfunction provide guidance . For this kind of research has been carried out a lot, mostly used in space flight and on the ground simulation method of weightlessness on the human body , human and animal experimental methods to become a major research tool , and has made some progress. However , due to objective conditions , it is difficult to obtain an ideal research conditions , many of the indicators in the existing conditions is difficult to obtain , and the approach taken to human trials to conduct research on the human body injury, animal experiments can not fully applicable to the human body. For the lack of human and animal experiments , in recent years carried out extensive computer simulation in this field study , insufficient to compensate for the experiment . In this study, drawing on previous studies of the base
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