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LSD is one of the most potent¹ hallucinogenic drugs—active at just around 100 micrograms…a miniscule amount. That fact has fascinated pharmacologists for decades. Namely, how can it have such long-lasting effects…12 hours or more…at such tiny doses?

麦角酸二乙基酰胺(简称LSD)是一种要效很强的迷幻药——只要一丢丢100毫克就可以起到作用。为此数十年来一直吸引着药理学家的目光。那就是，为什么会有这么长的药效呢…仅需微小的量就成持续12小时或者更长的时间?

To find out, researchers legally obtained LSD. And built copies of the receptors it binds² to in the brain—serotonin receptors. They mixed the LSD and the receptors together, and crystallized the result. They then imaged the structure, using x-ray crystallography.

为了找到问题的答案，研究人员依法获取了LSD，并获得了其在大脑中联接的受体——5-羟色胺受体的副本。之后研究人员将LSD和受体混合，明确最后结果。最后运用晶体学x射线对结构进行成像。

And they found that when LSD linked up with the serotonin receptor, a sort of "lid" formed over it. Almost like the drug went in, then pulled the door shut behind it. "You could think of the top part of LSD as a hand, holding onto the latch³ and pulling it down." Bryan Roth, a pharmacologist at University of North Carolina in Chapel⁴ Hill involved in the research.

研究人员发现，当LSD与5-羟色胺受体相连，就会形成一种“盖子”现象。就像药物进入，然后把门关上了。“你可以把LSD的上部分想象成一个手，抓住门闩并拉下来。”布莱恩·罗斯是北卡罗莱纳大学教堂山分校的药理学家，他参与了这项研究。

"This explains why LSD is so potent, why such a small amount of it is active, and secondly⁵ why it lasts for such a long period of time. Because basically once it gets in there it takes hours to come off the receptor." The study is in the journal Cell.

“这就解释了LSD如此强大,为什么其药效只需要微量,其次为什么它会持续这么长时间?因为只要其一旦进入，则需要数小时离开受体。该研究结果发表在《细胞》杂志上。

The result may also explain why microdosing—taking even smaller amounts of LSD, at sub-psychedelic levels—might work as a mood enhancer, as some users have reported. "It's clear from the data we have that these small doses can engage these receptors, and of course we know that the receptors that LSD interacts with, they're the same receptors that are thought to be involved in antidepressant drug action."

该结果也可以解释为什么微剂量——即使甚至很小量的迷幻药——都可以使情绪兴奋，这正如之前的使用者所说。“很明显，从我们获悉的数据，这些小量剂量可以与受体反应，同时LSD接触的受体，与抗抑郁药的受体是一样的。”

Roth does not advocate trying it out. But he says the discovery of the "lid" might someday lead to the development of novel antidepressants—ones with long-lasting effects, at just the tiniest of doses.

罗斯并不提倡进行研发试验。但是他表示，这样的“盖子”发现，或许在未来的某一天可以促进新型抗抑郁药的研发——只需要微剂量，就可以有长时间的效果。