“黑曼巴”是讓人聞之色變的非洲毒蛇，它的毒液可在20分鐘內(nèi)奪去一個(gè)人的生命,。但一項(xiàng)新研究顯示,，在這種蛇的致命毒液中藏有一種止痛效果堪比嗎啡的物質(zhì),，有望用于開發(fā)新型止痛藥,。
新一期英國期刊《自然》登載的報(bào)告說,，法國研究人員在對“黑曼巴”的毒液進(jìn)行分析后發(fā)現(xiàn),，其含有的一種由某類蛋白質(zhì)組成的物質(zhì)具有止痛效果。如果給實(shí)驗(yàn)鼠注射這種物質(zhì),，它們的爪子和尾部承受熱水灼燙的時(shí)間可以翻一倍，同時(shí)還可減輕與發(fā)炎相關(guān)的疼痛感,。
據(jù)介紹,，這類蛋白質(zhì)的止痛效果可與常用的強(qiáng)力止痛藥嗎啡相媲美,，但它卻沒有嗎啡的某些副作用,。比如注射嗎啡可能導(dǎo)致實(shí)驗(yàn)鼠的呼吸頻率降到危險(xiǎn)程度，但注射這類蛋白質(zhì)就不會出現(xiàn)這種現(xiàn)象,。
研究人員說,，實(shí)驗(yàn)鼠感受疼痛的機(jī)制與人相似,，因此有望在上述發(fā)現(xiàn)的基礎(chǔ)上開發(fā)新型止痛藥?，F(xiàn)在許多人對嗎啡等止痛藥產(chǎn)生了耐藥性,，但成功問世的新型止痛藥卻不多,，這項(xiàng)研究成果是止痛藥研發(fā)領(lǐng)域的一個(gè)好消息,。
不過研究人員也有一個(gè)疑惑不解的問題,，那就是“黑曼巴”作為毒蛇,，為何需在自己的毒液中合成止痛物質(zhì)。有研究者猜測這種物質(zhì)可能會與毒液中的其他物質(zhì)混合后發(fā)揮特殊作用，但還需進(jìn)一步研究加以證實(shí),。（生物谷Bioon.com）
doi: 10.1038/nature11494
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Black mamba venom peptides target acid-sensing ion channels to abolish pain
Diochot S, Baron A, Salinas M, Douguet D, Scarzello S, Dabert-Gay AS, Debayle D, Friend V, Alloui A, Lazdunski M, Lingueglia E.
Polypeptide toxins have played a central part in understanding physiological and physiopathological functions of ion channels. In the field of pain, they led to important advances in basic research and even to clinical applications. Acid-sensing ion channels (ASICs) are generally considered principal players in the pain pathway, including in humans. A snake toxin activating peripheral ASICs in nociceptive neurons has been recently shown to evoke pain11. Here we show that a new class of three-finger peptides from another snake, the black mamba, is able to abolish pain through inhibition of ASICs expressed either in central or peripheral neurons. These peptides, which we call mambalgins, are not toxic in mice but show a potent analgesic effect upon central and peripheral injection that can be as strong as morphine. This effect is, however, resistant to naloxone, and mambalgins cause much less tolerance than morphine and no respiratory distress. Pharmacological inhibition by mambalgins combined with the use of knockdown and knockout animals indicates that blockade of heteromeric channels made of ASIC1a and ASIC2a subunits in central neurons and of ASIC1b-containing channels in nociceptors is involved in the analgesic effect of mambalgins. These findings identify new potential therapeutic targets for pain and introduce natural peptides that block them to produce a potent analgesia.
