英伦广角 晒日光浴的老鼠会上瘾（在线收听）

You may love to soak up the sun—or the UV rays at the tanning salon. But are you actually addicted?

你可能喜欢晒日光浴，或者喜欢去日光浴沙龙晒紫外线。但是你会真的上瘾吗?

A study finds that mice regularly exposed to UV produced the feel-good opioid β-endorphin, and behaved like addicts.

一项研究表明老鼠定期暴露在紫外线下会产生类似吸食鸦片般感觉的内啡肽，而且行动起来也像上瘾的一样。

What’s more, when they were given a drug that blocked the opioid effects, they went through the rodent equivalent of withdrawal: shaky paws and chattering teeth. The study is in the journal Cell. [Gillian L. Fell et al, Skin β-Endorphin Mediates Addiction to UV Light] (To hear an interview with study author David E. Fisher, go to the Cell website.)

而且，当给他们喂食药品来阻止类似鸦片效果的产生时，他们就会经历啮齿类动物戒毒般的感觉：摇摇晃晃的爪子和颤颤抖抖的牙齿。这项研究发表在《细胞》杂志上。

The mice were exposed to UV light roughly on par with a fair-skinned human soaking up a half-hour of Florida midday sun, five days a week for a month-and-a-half. But it took just one week for the endorphin levels to zoom.Mice are normally nocturnal and, of course, covered by fur. But the research team says that the apparent physical reward for UV exposure suggests it’s worth exploring if a similar chemical reaction may be spurring humans to keep running to the beach or tanning bed.

老鼠一个月半每周五天暴露在在紫外线下大致相当于一个白皮肤的人吸收半小时佛罗里达中午的阳光。但是老鼠仅仅花费一周就可以让其脑内啡值急剧上升。老鼠一般是夜间行动，当然它身体还被毛覆盖。然而研究小组却称，这明显的应对紫外线的身体优势表明，这值得探索相同的化学反应是否会激励人类一直奔跑在沙滩上或者一直享受日晒床上的时光。

They also say it’s likely sunblock would protect against these UV-induced addictive behaviors. Yet another reason to slather on the sunscreen.—Dina Fine Maron

他们也说这很像防晒霜，可以防范紫外线成瘾行为。这也是人类涂抹防晒霜的另一种原因。