间斑寇蛛粗毒液的生理生化分析及两种采毒方法的比较

Venom Properties of the Spider Latrodectus tredecimguttatus and Comparison of Two Venom-Collecting Methods

利用两种不同方法采集间斑寇蛛(Latrodectus tredecimguttatus)毒液并对其进行理化和生物学性质的比较分析。结果显示,粗毒液中的蛋白质成分主要是相对分子质量较大(>104)的酸性蛋白质。与毒囊粗毒液相比,电刺激粗毒液中相对分子质量在105左右的蛋白质含量明显高于毒囊粗毒液中的含量,而两者中相对分子质量较小(<104)的蛋白质与多肽的组成非常相似。电刺激粗毒冻干粉和毒囊粗毒冻干粉对小白鼠的LD50值分别为(0.16±0.03)mg/kg和(0.39±0.05)mg/kg体重;对美洲蜚蠊(Periplaneta Americana)的LD50值分别为1.87μg/g和2.32μg/g。在浓度为3.2×10-6g/mL时,电刺激粗毒冻干粉能在(25.0±2.2)min内完全阻断小鼠膈神经-膈肌标本的神经肌肉接头传递;毒囊粗毒冻干粉在浓度为6×10-6g/mL时的完全阻断时间为(23.3±2.2)min;粗毒液中的低相对分子质量(<104)部分在10-4g/mL浓度下对标本的神经肌肉接头传递无明显影响。上述结果表明,间斑寇蛛毒液是一种富含大分子量蛋白质的混合物;哺乳动物神经毒性主要基于其中的大的相对分子质量酸性蛋白质成分,而不是低的相对分子质量的多肽;电刺激粗毒液中的活性成分与毒囊粗毒液中的相似,但含量高于毒囊粗毒液。

The bioactivities and proteinous compositions of venoms collected by two different methods from Latrodectus tredecimguttatus were analyzed and compared. Most of proteinous venom components were high-molecular-mass acidic proteins （〉10^4）. Compared with the venom obtained from dissected venom gland （DGV）, the venom obtained by electrical stimulation （ESV） contained more high molecular mass proteins, but the venom proteins and peptides with low molecular mass （〈10^4） in the preparations were very similar. Intraperitoneal injection of the two venoms in mice gave rise to similar poisoning symptoms and the LD50 values of ESV and DGV were （0.16 ± 0.03）mg/kg and （0.39±0.05）mg/kg, respectively. LD50 values of ESV and DGV in cockroaches （Periplaneta Americana） were 1.87 μg/g and 2.32 μg/g, respectively. ESV was able to block neuromuscular transmission in the mouse phrenic nerve-hemidiaphragm preparation within （25.0±2.2）min at a concentration of 3.2× 10^6g/mL, whereas DGV blocked neuromuscular transmission within （45.7 ± 1.8）min at the same concentration. The fraction of the venom containing proteins and peptides with molecular mass 〈 10^4 did not obviously affect the transmission. Those results demonstrated that Latrodectus tredecimguttatus venom was a mixture rich in larger proteins rather than smaller proteins and peptides; the mammalian toxicities of the venom were due primarily to the high molecular weight acidic proteins rather than low molecular weight peptides; the active components contained in ESV and DGV were similar but the content in ESV was higher than that in DGV.