目的研究不同膜脂对米氏凯伦藻溶血作用的影响。方法于反应体系中加入外源性卵磷脂、鞘磷脂、L-α-磷脂酸、胆固醇和神经节苷脂等5种膜脂,观察其对米氏凯伦藻溶血毒素活性的影响;分析溶血毒素对不同动物红细胞的溶血活性,比色法测定不同动物红细胞膜中神经节苷脂的总量。结果 5种膜脂中,只有神经节苷脂对溶血活性具有显著的抑制作用(P〈0.05)。加入神经节苷脂10min后,其溶血活性仅为16.05%,而对照组为35.65%。兔红细胞对毒素最为敏感,溶血百分数明显高于相应大鼠(P〈0.05)和美国红鱼(P〈0.01);兔、大鼠和美国红鱼每克冻干红细胞膜上脂结合唾液酸(LBSA)的量分别为672.08、585.97和431.52μg/g,兔红细胞膜上LBSA量显著高于大鼠和美国红鱼(P〈0.05)。结论外源神经节苷脂可显著抑制米氏凯伦藻溶血毒素的活性,不同动物红细胞对毒素的敏感性与其红细胞膜上神经节苷脂的量呈明显相关。
Objective To explore the effects of some membrane lipids on the hemolysis induced by hemolytic toxin from Karenia mikimotoi.Methods Effects of exogenous membrane lipids such as lecithin,sphingomyelin,L-α-phosphatidic acid,cholesterol and gangliosides on the hemolysis induced by the hemolytic toxin were observed.The sensitivities of some erythrocytes from different animals such as rabbit,rat and fish to the hemolytic toxin were evaluated.The total gangliosides in different erythrocytes membrane were detected by colorimetry.Results Only gangliosides significantly inhibited the hemolysis of the hemolytic toxin from K.mikimotoi(P0.05).Hemolytic percentages decreased to 16.05% after 10min addition of ganglioside,while those of control were 35.65%.The rabbit red blood cell was the most sensitive to the hemolytic toxin.The hemolytic percentages of rabbit erythrocyte were higher than those of rat(P0.05) and fish(P0.01).The amounts of lipid-bind sialic acid(LBSA) on frozen dried membrane of rabbit were 672.08μg/g,and were higher than those of rat(585.97μg/g)(P 0.05) and that of fish(431.52μg/g)(P0.01).Conclusion Exogenous gangliosides could have a potent inhibition on the hemolysis induced by hemolytic toxin from K.mikimotoi.There was a significant correlation between the sensitivities of different erythrocytes to the hemolytic toxin and the amount of ganglioside on different erythrocytes membrane.