毒理性
夹竹桃苷植物中毒在儿童中很常见,而且该植物提取物在中国医药中使用。其毒性主要是由夹竹桃苷和去糖基代谢物夹竹桃苷元引起的。蟾酥素和蟾酥总苷(蟾蜍心脏毒素)在中国医药中,如蟾酥、鹿肾五(Chan SU,和 Lu-Shen-WU)也广泛使用。食用蟾蜍汤后,蟾酥素引起的严重毒性已有报道。利用这些毒素与地高辛的结构相似性,我们证明了这些化合物可以通过荧光偏振免疫分析法快速地在血液中被检测出来。这些化合物与地高辛检测的交叉反应要低得多。例如,当不含药物的血清中加入10微克/毫升的夹竹桃苷时,我们观察到相当于127.7纳克/毫升的地高辛,但仅相当于2.4纳克/毫升的地高辛浓度。Digibind中和了我们研究中所有的心脏毒素,自由浓度显著下降。当含有50.0微克/毫升夹竹桃苷的血清池中加入0、10.0、25.0、50.0、100和200微克/毫升的Digibind时,平均自由浓度分别为30.6、23.3、16.0、10.7、7.8和5.5微克/毫升。同样,对于含有50.0微克/毫升夹竹桃苷元(总浓度:36.2纳克/毫升)的样品,在没有Digibind的情况下,自由浓度为14.5纳克/毫升地高辛当量,而在存在200微克/毫升Digibind的情况下为5.4纳克/毫升。在另一个含有500纳克/毫升蟾酥素(总浓度:156.9纳克/毫升)的标本中,在没有Digibind的情况下自由浓度为8.6纳克/毫升,而在存在100.0微克/毫升Digibind的情况下未检测到。因为这种中和也可能在体内发生,所以Digibind可能对治疗接触这些毒素的患者有用。
Oleandrin plant poisoning is common in children and the plant extract is used in Chinese medicines. The toxicity is due to oleandrin and the deglycosylated metabolite oleandrigenin. Bufalin and cinobufotalin (toad cardiac toxins) are also widely used in Chinese medicines like Chan SU, and Lu-Shen -WU. Severe toxicity from bufalin after consumption of toad soup has been reported. Taking advantage of structural similarities of these toxins with digitoxin, we demonstrated that these compounds can be rapidly detected in blood by the fluorescence polarization immunoassay for digitoxin. The cross reactivities of these compounds with digoxin assay were much lower. For example, when a drug free serum was supplemented with 10 ug/mL of oleandrin, we observed 127.7 ng/mL of digitoxin equivalent but only 2.4 ng/mL of digoxin equivalent concentration. Digibind neutralized all cardiac toxins studied as evidenced by significant fall of free concentrations. When aliquots of serum pool containing 50.0 ug/mL of oleandrin were supplemented with 0, 10.0, 25.0, 50.0, 100, and 200 ug/mL of digibind, the mean free concentrations were 30.6, 23.3, 16.0, 10.7, 7.8 and 5.5 ug/mL respectively. Similarly, with 50.0 ug/mL of oleandrigenin (total concentration: 36.2 ng/mL), the free concentration was 14.5 ng/mL digitoxin equivalent in the absence of digibind and 5.4 ng/mL in the presence of 200 microg/mL of digibind. In another specimen containing 500 ng/mL bufalin (total concentration: 156.9 ng/mL), the free concentration was 8.6 ng/mL in the absence of digibind and none detected in the presence of 100.0 ug/mL digibind. Because such neutralization may also occur in vivo, digibind may be useful in treating patients exposed to these toxins.
来源:Hazardous Substances Data Bank (HSDB)