Oxygen Carrying Capacity of Totally Synthetic Oxygen Carrier-Lipidheme-Microsphere-

用合成脂素覆盖临床可用的脂肪滴（甘油三酯微球），生成完全合成的载氧物质（人工红细胞）。因此，脂肪滴被用作脂素载体作为氧载体。该人造红细胞替代品的尺寸为103 <正负bbb29nm。比重、粘度和渗透压与人体血液非常相似。体外氧结合可逆，速度快，P50为40mmHg。血液中的半衰期为10-13小时，在循环血容量高达60%的比格犬中交换输血表明，这种红细胞替代品向组织输送的氧约为50ml/min，约占总氧输送量的40%。该氧载体耗氧量为25ml/min，约占总耗氧量的25%。在高达80%的交换输血中，由于严重的低白蛋白血症引起的肺水肿，很难保持比格犬的存活。为了继续实验，有必要采用全体外循环。另一种想法是制造具有致氧压力的人工氧载体。我们现在用嵌入了脂素的白蛋白来制造这种材料。作为灌注白蛋白是强制性的，以增加胶质肿瘤压力到这个脂素微球。白蛋白具有胶质致瘤压力，作为脂质血红素的载体作为氧载体。

Totally synthetic oxygen carrying substance (artificial red cell) was produced by covering clinically available fat droplets (triglyceride microsphers) with synthetic lipidhemes. Thus fat droplets were used as vehicles of lipidhemes as oxygen carrier. The size of this artificial red blood cell substitute is 103 <plus-minus> 29nm. Specific gravity, viscosity and osmotic pressure were very similar to that of human blood. In vitro study its oxygen binding was reversible and fast, the P50 was 40mmHg. Half life time in blood was 10-13 hourExchange transfusion in beagles upto 60% of circulating blood volume showed that oxygen transport to the tissue by this red blood substitute was about 50ml/min which corresponded about 40% of total oxygen transport. Oxygen consumption from this oxygen carrier was 25ml/min which corresponded about 25% of total oxygen consumption. In exchange transfusion upto 80%, it was difficult to keep beagles alive because of pulmonary edema due to severe hypoalbuminemia. To continue experiment it was necessaty to use total cardiopulmonary bypass. Another idea is to produce artificial oxygen carrier which has oncotic pressure. We are now producing this kind of material by using albumin in which lipidhemes are embedded. As perfusate albumin was mandatory to increase colloid oncotic pressure to this lipidheme microsphere. Albumin which has colloid oncotic pressure, is used as vehicles of lipid heme as oxygen carrier.