What does the liver do? - Emma Bryce

肝臓の働き - エマ・ブライス

翻訳: Masako Kigami 校正: Masaki Yanagishita

There's a factory inside you that weighs about 1.4 kilograms

体内には 重さ1.4キロで

and runs for 24 hours a day.

１日24時間営業の工場があります

This is your liver, the heaviest organ in your body,

それは肝臓です 体内で一番重い臓器で

and one of the most crucial.

最も重要な臓器の一つです

This industrious structure simultaneously acts as a storehouse,

肝臓は同時に貯蔵所

a manufacturing hub,

製造拠点

and a processing plant.

処理工場の三役をこなします

And each of these functions involve so many important subtasks

これらすべての機能には 多くの重要な役割があり

that without the liver, our bodies would simply stop working.

肝臓なくしては 生命活動が止まってしまうほどです

One of the liver's main functions is to filter the body's blood,

肝臓の主な働きの一つは 体内の血液をろ過することです

which it receives in regular shipments from two sources:

２つの臓器から－ 心臓から肝動脈を通して

the hepatic artery delivers blood from the heart,

腸から肝門脈を通して

while the hepatic portal vein brings it from the intestine.

休まず血液が運ばれます

This double delivery fills the liver with nutrients,

この２か所からの血液で 肝臓が栄養で満たされます

that it then sorts, processes and stores

そして小葉という何千もの小さな

with the help of thousands of tiny internal processing plants,

体内処理工場と協力し合って

known as lobules.

仕分け､処理､貯蔵をするのです

Both blood flows also deliver the oxygen that the liver needs to function.

血液は 肝臓が機能するのに必要な酸素も送ります

The blood that is received from the intestine

腸からの血液は

contains carbohydrates, fats,

摂取した食べ物に含まれている

and vitamins and other nutrients dissolved in it

炭水化物や脂質

from the food you've consumed.

ビタミンやその他の栄養素を含んでいます

These must be processed in different ways.

これらは異なる方法で処理される必要があります

In the case of carbohydrates,

炭水化物の場合は

the liver breaks them down and converts them into sugars

肝臓で分解 糖質に変換され （注：正しくは口から小腸のまでの消化過程による）

for the body to use as energy when the filtered blood is sent back out.

肝臓から送り出された血液は 全身にエネルギーを供給します

Sometimes the body has leftovers of nutrients

時々すぐには必要とされない

that it doesn't immediately require.

栄養素が体内に残ります

When that happens, the liver holds some back,

そういう場合に肝臓は

and stacks them in its storage facility.

保管施設に貯蔵します

This facility works like a pantry

この施設は 将来体が栄養を必要とした場合の

for future cases when the body might be in need of nutrients.

食品貯蔵室として機能します

But the blood flowing into the liver isn't always full of good things.

でも 肝臓に入る血液が常に 良いものばかりとは限りません

It also contains toxins and byproducts that the body can't use.

毒素や体が使えない副産物もあるのです

And the liver monitors these strictly.

肝臓はこれらを厳しく監視し

When it spots a useless or toxic substance,

役に立たないものや 有害物質を見つけると

it either converts it into a product that can't hurt the body

体に害を与えない物質に変えるか

or isolates it and whisks it away,

血液から分離して除去し

channeling it through the kidneys and intestine to be excreted.

腎臓や腸を通じて排出します

Of course, we wouldn't consider the liver a factory

もちろん 肝臓が何も作らないのなら

if it didn't also manufacture things.

肝臓を工場とは考えません

This organ makes everything from various blood plasma proteins

肝臓は脂肪酸を運んだり 血液凝固を促す

that transport fatty acids and help form blood clots,

様々な血漿タンパク質から ホルモンの原料となる

to the cholesterol that helps the body create hormones.

コレステロールまで作ります

It also makes vitamin D and substances that help digestion.

また ビタミンDや 消化を促す物質まで作ります

But one of its most vital products is bile.

生命に関わる物質の一つが胆汁です

Like an eco-friendly treatment plant,

環境に優しい処理場のように

the liver uses cells called hepatocytes

肝臓は肝細胞という細胞を使って

to convert toxic waste products into this bitter greenish liquid.

有害ゴミを 苦い 緑色がかった液体に変えます

As it's produced, bile is funneled into a small container below the liver,

それが作られると 肝臓の下にある

called the gallbladder,

胆嚢に送ります

before being trickled into the intestine

次に胆汁が腸に流れ出ると

to help break down fats, destroy microbes, and neutralize extra stomach acid.

脂肪を分解し 病原菌を殺し 胃酸を中和する働きがあります

Bile also helps carry other toxins and byproducts from the liver

胆汁は体外に 肝臓からの毒素や副産物を

out of the body.

排出するのにも役立ちます

So as you can see,

ご覧の通り

the liver is an extremely efficient industrial site,

肝臓は究極の効率を誇る 工場で

performing multiple tasks that support each other.

複数の役割が 互いに助け合っています

But such a complex system needs to be kept running smoothly

このように複雑な臓器は 健康を保ち

by keeping it healthy

許容範囲を超える毒素で

and not overloading it with more toxins than it can handle.

過重な負担をかけないよう 滑らかに機能させる必要があります

This is one factory we simply can't afford to shut down.

これは閉鎖など考えられない 工場なのです