Name: 動物研究對大腦有什麼作用？ (What has animal research done for the brain?)
Uploaded: 2021-01-14T05:11:40.000Z
Duration: 28 min 22 s
Description: 【看影片學英語】數萬部 YouTube 影片，搭配英漢字典即點即查，輕鬆掌握單字發音與用法，長久累積看電影不必再看字幕。

Behind every disease statistic there is a person

Lucy suffers from a disorder affecting a part of her brain that controls movement

基礎被動語態

before her operation she was confined to a chair and had difficulty eating and

without surgery that could only have been developed through animal research

the brain is the most complex organ in our body

it is not just a sum of all its component  pieces

indeed, it is one of the most complex organ we have ever tried to understand

and how it does what it does, is still largely a mystery

this means that research techniques focusing on a small part of the brain or

single pathway cannot tell the whole story

the brain controls every aspect of our lives

from regulating our heartbeat and emotions to movement and speech

however, unlike a heart or any other organ it can't be replaced

and at the moment, there are no cures for diseases of the brain

some disorders affecting the central nervous system are genetically driven

as a child you have no influence on your genetic makeup

which could predispose you to disorders like Schizophrenia

in addition anyone of us could have an accident and be left paralyzed

well the common causes of spinal cord injury are things that

could happen in everyday life, so they are things like automobile accidents

and also for example, a lot of sporting injuries can cause spinal cord injury

and if we take the famous case of Christopher Reeve, he actually fell off his horse

but at the moment there are a number of experimental techniques which are being

developed which may potentially be the treatments of tomorrow for treating

so at the moment the majority of research looking at spinal cord injury, involves

and what we do is, we look at the ability of a chemical, an enzyme called

Chondroitinase, which has being shown to allow regeneration of nerve fibres

in the spinal cord, to quite considerable distances.

scar tissue forms, it is partly comprised of the cell type called ghlea

this acts as a physical barrier to nerve regrowth.

it's thought to break down the constituents of the gleaus scar and therefore reduce

You couldn't do this on humans for a number of reasons, the first major reason

is because Chondroitinase is actually toxic to humans, so the doses that you

would require to get functional recovery are just too great

but using our animal models we can look at this drug and we can look at the

active sites and how it could actually exert its action

and divise an analogue pharmaceutically which could then be used in humans

the second reason is obviously that you can't look at histology

you can't look at post mortem of patients because you have to wait a very long

time for them to actually expire and then to remove the spinal cord, whereas

with rats it allows us to do this over a relatively short period of time.

The same problems hold true when using post-mortem brains to study mental illness

the drawback of studying things in post mortem brain is of course people have typically

and they have been exposed to 30, 40 years of drug treatment

and a very isolated kind of existence, so it's diffcult to find controlled people

you can't match the effects of the drug and you can't match the effect of lifestyle

The difficulties in using human tissues are partly overcome by using animals, whose environment we

in the case of an introduced spinal cord injury

the animal still has normal function in one side of the body

this means that the recovery following treatment in the injured side

can be compared with the normal in a series of behavioral tests.

There is something called the sticky tape test

and essentially what this involves is a piece of sticky tape attached to the

and it has to sense that this sticky tape is there and because it's not very

comfortable for the animal it will then rip off the sticky tape

and therefore you can assess 2 things you can assess the sensory

regained after application of Chondroitinase because it can feel the sticky tape

and also the motor responses because in order to pull it off

mice are placed inside a small chamber where they have to walk along the stationary

platform to retrieve the series of tiny sugar treats

they can only use the right port to reach the right stair case

animals with the spinal lesion on one side

finds this difficult to do on the side that is injured.

commonly used to assess memory impairment following stroke

animals have to find a submerged platform hidden in a murky pool of water

they use visual cues from around the room

the position of the door or window for example

once they find it they are taken out of the pool, towel dried and back to cage

those that struggle with the task are fished out after a couple of minutes.

In spinal cord injury, the challenge is to regenerate the damaged nerve cells