播客 1007：咖啡因药理学

这里是急诊医疗一分钟。

This is the Emergency Medical Minute.

本节目由CarePoint和HCA HealthONE赞助。

Sponsored by CarePoint and HCA HealthONE.

今天我本来想讲讲全球消费量最大的一种药物。

So I was going to do a medical minute today on the drug that is probably most consumed across the planet.

那就是咖啡因。

And that is caffeine.

你和你丈夫。

You and your husband.

没错。

Exactly.

咖啡因特别有意思，它出现在多种植物里，而这些植物各自独立演化，分布在地球的不同地方。

So caffeine, super interesting, has been found in plants that all independently evolve from each other and are in different parts of the planet.

比如非洲的咖啡。

So we've got coffee in Africa.

中国和印度有茶。

There's tea in China and India.

南美洲有马黛茶。

Yerba mate in South America.

瓜拉纳和可可也有。

Guarana, cocoa.

在北美洲，我们还有雅浦昂冬青。

And then in North America, we also have the yaupon holly.

这些植物各自独立演化出了咖啡因。

All these plants independently evolved caffeine on their own.

这挺有意思的，而且我们知道植物里的咖啡因其实是一种杀虫剂。

So that's kind of interesting and we actually know that caffeine in plants is an insecticide.

昆虫吃下去后会中毒，相当于喝过量了。

So it kills insects as they eat it and they kind of, they overdose on it basically.

这还挺有意思的。

So that's kind of neat.

我们人类文化也各自找到了摄入咖啡因的方式。

We also as a culture all independently found ways to consume caffeine.

不管是喝咖啡、喝茶、吃可可，还是别的形式，我觉得这也挺有意思的。

So whether it's as coffee or tea or drinking cocoa or whatever, I think that's also kind of cool.

所以到了今天，大约有百分之八十到八十五的美国人每天都会摄入咖啡因。

So that brings us to today where now roughly eighty to eighty five percent ish of Americans consume caffeine every day.

我们并不清楚到底有多少人对咖啡因上瘾，但它已经深深融入了我们的日常生活。

And we don't know exactly how many are actually addicted to caffeine, but it is definitely entrenched in our culture.

有人知道咖啡因在体内是怎么起作用的吗？

Does anyone know how it works on the body?

它到底对身体做了什么？

Like what it does?

它会接管你的身体，是吧？

It takes over your Yeah?

它模仿你的腺苷，掩盖了你的疲惫感，你差不多说到点上了。

And it mimics your sink, and it kind of covers up your Yeah, you're getting there.

它是一种腺苷受体阻断剂。

It's an adenosine receptor blocker.

阻断剂。

Blocker.

简单说，当你醒来并度过一整天时，你的神经元会不断消耗ATP。

So basically, as you wake up and go throughout your day, your neurons are churning through ATP.

同时产生腺苷，这种物质会积累并让你产生困意。

And they are producing adenosine, which builds a sleep pressure.

所以随着一天过去，腺苷越积越多，你就越来越想睡觉。

So basically as you go throughout the day, you build more and more and more adenosine, and you feel sleepier and sleepier and sleepier.

而咖啡因会阻断腺苷受体，于是你就保持清醒的状态。

And caffeine blocks the adenosine receptors, And so then you feel this state of wakefulness.

咖啡因的半衰期大约是六个小时。

The half life of caffeine is about six hours.

所以四分之一衰减期大概在十二小时左右。

So that puts a quarter life at about twelve hours.

所以大概六到十二小时左右，咖啡因就会从那些受体上脱离下来。

So somewhere around six to twelve hours ish, you will then have it offload from those receptors.

然后你就会接触到大脑里积攒的那些咖啡因。

And you'll get exposed to all that caffeine that's been circulating in your brain.

抱歉，我是说，大脑里积攒的那些腺苷会一下子释放出来。

And you'll I mean, sorry, all that adenosine that's been circulating in your brain.

接着你就会感到一阵强烈的困倦。

And you'll then get that crash.

这对值夜班的人特别重要，咱们部门的人不就是典型例子吗。

This is super relevant for shift workers, which is us in the department, obviously.

如果你打算控制喝咖啡的时间来帮助入睡，最好在目标睡觉时间前十小时左右，或者更早之前就别喝了。

It's recommended that if you are trying to time when to drink caffeine best to like get to sleep, You want to drink it somewhere roughly maybe ten hours ish before your target bedtime or earlier.

咖啡因对大脑和身体还有其他影响。

Caffeine has other effects on brain and body.

它还属于甲基黄嘌呤类药物，比如茶碱，就是我们用来治疗哮喘的一种药。

Also is part of the class of drugs called methylxanthine, which includes theophylline, which is a drug that we give for asthma.

所以它确实有点扩张支气管的作用，能让肺部的气道稍微放松一点。

So it does have slightly bronchodilatory effects, so it can cause a little bit of bronchodilation in the lungs.

它还有利尿作用，会增加钠和氯的排泄。

It's also diuretic and causes increased sodium chloride reabsorption.

其实是抑制了重吸收。

Actually, prevents that.

我觉得特别有意思的是，这种物质在世界各地、多种植物里都独立演化出来了，到处都是。

So anyway, I just think it's super interesting that this drug is widely prevalent, multiple cultures, multiple plants, independently evolved, it's so ubiquitous.

我们平时见得太多了。

And we see it all the time.

如果病人在我们给腺苷治疗室上速之前喝了大量咖啡因，那腺苷的效果肯定会打折扣。

It is also the case that if a patient had consumed a ton of caffeine before we were to say, let's say give them adenosine for SVT, it definitely is less effective.

所以这也是个值得注意的小细节，毕竟咖啡因对心脏也有影响。

So kind of a cool little caveat to remember that also obviously has effects on the heart.

大家还有什么别的想法吗？

Does anyone have any other comments?

今天谁喝过咖啡因了？

Who here drank caffeine today?

我也是。

Same.

我现在就在喝。

I'm drinking some right now.

所以不管怎样，这算是对日常生活中再平常不过的东西做了一次有趣的深入探讨。

So either way, kind of just a little cool deep dive on something that is just part of our day to day lives.

以上就是急诊医学小贴士。

This has been the emergency medical minute.

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Thank you to our sponsors CarePoint and HCA HealthONE.

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