Huxtable R J
Department of Pharmacology, College of Medicine, University of Arizona, Tucson 85724.
J Ethnopharmacol. 1992 Aug;37(1):1-11. doi: 10.1016/0378-8741(92)90002-9.
It is impossible to predict what compounds of pharmacological interest may be present in an unexamined species. The extinction of such species may result, therefore, in the loss of therapeutically significant compounds. The fact that science will never know what has been lost does not lessen the significance of the loss. A number of species are discussed to exemplify the potential loss. Ginkgo biloba is an ancient plant, apparently saved from a natural extinction by human intervention. From this tree, the ginkgolides have been isolated. These are potent inhibitors of platelet activating factor and hold promise in the treatment of cerebral ischemia and brain edema. Two species, the tree Taxus brevifolia and the leech Hirudo medicinalis, are threatened as a result of human activity. Both have recently yielded complex compounds of therapeutic importance. The antitumor agent, taxol, is obtained from T. brevifolia and the thrombin inhibitor, hirudin, is found in H. medicinalis. Catharanthus roseus, source of the anticancer agents vincristine and vinblastine, although not threatened, derives from a largely unexamined but severely stressed ecosystem of some 5000 plant species. In other examples, ethnobotanical knowledge of certain plants may be lost while the species survive, as exemplified by the suppression of the Aztec ethnobotany of Mesoamerica by the invading Spanish. Finally, the fallacy of the 'snail darter syndrome', where species may be viewed as too insignificant to worry about, is exposed by consideration of the pharmacological activities of a sea hare (a shell-less marine mollusc) and various leeches.
无法预测在一个未经研究的物种中可能存在哪些具有药理学意义的化合物。因此，此类物种的灭绝可能导致具有治疗意义的化合物流失。科学永远无法知晓所失去的东西，这一事实并不会降低这种损失的重要性。文中讨论了一些物种以例证这种潜在的损失。银杏是一种古老的植物，显然因人类干预而免遭自然灭绝。从这种树上分离出了银杏内酯。这些是血小板活化因子的强效抑制剂，在治疗脑缺血和脑水肿方面有前景。两种物种，短叶红豆杉树和药用水蛭，因人类活动而受到威胁。两者最近都产生了具有治疗重要性的复杂化合物。抗肿瘤药物紫杉醇是从短叶红豆杉中提取的，凝血酶抑制剂水蛭素则存在于药用水蛭中。长春花是抗癌药物长春新碱和长春碱的来源，虽然未受到威胁，但它来自一个约5000种植物的大部分未经研究但受到严重压力的生态系统。在其他例子中，某些植物的民族植物学知识可能在物种存活的情况下丧失，例如中美洲阿兹特克民族植物学被入侵的西班牙人压制的例子。最后，通过考虑海兔（一种无壳海洋软体动物）和各种水蛭的药理活性，揭示了“蜗牛镖鱼综合症”的谬误，即物种可能被视为太微不足道而无需担忧。
