北部湾金黄水母Chrysaora helvola Brandt刺细胞毒液溶血活性

【目的】探讨金黄水母Chrysaora helvolaBrandt刺细胞毒液(nematocysts venom,NV)的红细胞溶血活性特征及可能机制。【方法】通过分光光度法测定红细胞溶解释放血红蛋白的量来确认不同条件和药物对NV诱导红细胞溶血行为的影响。【结果】NV诱导的红细胞溶血与其总蛋白浓度存在依赖关系。溶液pH值、大分子非电解质渗透压保护剂PEGs均能显著影响其溶血活性;非电解质小分子糖类渗透压保护剂D-甘油和D-半乳糖对溶血活性影响很小,但D-葡萄糖能显著延缓溶血。NV同时具有Ca~(2+)依赖的弱磷酸酯酶A2(PLA_2)活性,且受组氨酸烷基化试剂p-BPB抑制。这一PLA2活性可能对其红细胞溶血活性也有贡献。【结论】NV的红细胞溶血活性可能由膜穿孔机制和所含PLA_2酶成分造成,并受到含葡萄糖单元结构的糖受体调节。

An in vitro Study on the Erythrocytes Hemolytic Activity of the Nematocysts Venom from Chrysaora helvola Brandt

Objective] The characterization and possible mechanisms of the erythrocytes hemolysis induced by nematocysts venom from the Chrysaora helvola Brandt jellyfish were discussed.Methods] The hemoglobin content released from hemolysis was calorimetrically determined in the presence of NV only or NV and other reagents.Results] A concentration-dependent hemolytic effect of the NV was revealed.The solution pH as well as non-electrolytic osmotic protectants with high molecular weight, such as PEGs, can significantly affect the hemolysis induced by the NV.Non-electrolytic osmotic protectants, D-glycerol and D-galactose, have no sig-nificant effect on the hemolysis, while D-glucose can effectively retard it.Weak enzymatic activity of phospholipase A₂ was also detected in the NV.This PLA₂ activity is Ca²⁺-needed and can be inhibited by the alkylating reagent p-BPB.Inhibition of the PLA₂ enzymatic activity can partially inhibit the hemolysis induced by the NV.Conclusion] The hemolysis induced by NV from C.helvolais possibly caused by the membrane pore-forming mechanism and its PLA₂ ingredient, and mediated by glucose-containing receptors.