Heart Muscle

Chucky

Hey


Are the cells found in heart muscle renewed like other cells around the body?

Kevin.

Vorsprung

no, they are permanent cells, like neurons and skeletal muscle, so they can't regenerate. as far as i can remember anyway!

John

bigjimthefirst wrote:

no, they are permanent cells, like neurons and skeletal muscle, so they can't regenerate. as far as i can remember anyway!

Skeletal muscle can renew itself but cardiac can't.

Chucky

Thanks for the replies. Do you think this is an area that evolution could eventually change to prolong life even further?

John

Evolution doesn't work like that. Evolution is all chance. If by chance enough genes mutated that all working together would allow cardiac muscle to regenerate and the individual it happened in managed to have kids then there's a good chance it would spread through the gene pool in a population. I find it hard to believe that it could happen though. I'd say the best bets of seeing regeneration will be from stem cell research.

Chucky

Hehe, I know how evolution works - I was speaking very generally though. I don't see why it couldn't happen though. There would be no difficulties with cardiac muscle regenerating I assume

John

It could happen but the chances of it happening are slim. Not only that it would take hundreds of thousands of years at a very generous estimate, more likely in the millions and to be honest with the way we're abusing the environment I don't see mankind existing for that long.

Chucky

I like your thinking - I cannot see mankind existing for the rest of the habitable lifetime of Earth either. We aren't good hosts for this beautiful planet. I believe that a microorganism will rise to become the only living organism eventually.

John

Well microorganisms already rule the earth, you find them in more places than anything else. We're just guests at their party.

Chucky

Nicely put my friend! Anyway, thank you for the answers on the cardiac muscle. I was nearly sure that cardiac cells weren't renewed but my brother made me unsure.

DrIndy

Cardiac cells do not renew themselves unlike other muscle cells - however, the nearby cells compensate by increasing in size to take over the load of the damaged ones.

There is new research where growth factors/stem cells are injected into the areas of damaged tissue which allows it to regenerate itself and repair the areas after a heart attack.

John

I thought skeletal muscle could renew itself? If the muscle atrophies can't it be built back up with exercise?

DrIndy

skeletal muscle regenerates to a small extent, primarily the response is to increase in size, rather than cells dividing. If there is an infarct to skeletal muscle, then some cells can renew into muscle again - but to a limited extent.

Heart muscle does not divide at all and after an infarct (cell death due to loss of blood supply) - then it forms scar tissue, leaving a permanent defect in its ability to contract.

John

And that's why you're the doctor.

Chucky

Thank you for the replies my friends


I have a question though: Could excessive exercise ever result in cardiac muscle being overworked, and then result in permanently damaged cardiac cells?


Like my thinking now is that all of this jogging and cycling I have been doing during my life might actually be slightly damaging some of my cardiac cells.

DrIndy

Your heart naturally hypertrophies (increases in size) in response to training - but in normal physiology, this is normal response.

You would need actual disease to your heart such as coronary artery disease to do real damage.

Chucky

Thank you

derek27

indeed heart muscle can undergo hypertrophy (but not proliferation) but no matter how much you exercise, being highly active doesn't generally result in hypertrophy of cardiac muscle cells. rather, if hypertrophy is seen to occur (resulting in an enlarged heart), the underlying etiology is usually related to ill health effects such as high blood pressure or heart valve diseases which puts the undue stress on heart muscle causing the hypertrophic response.

Chucky

This is a rather obscure question on its own but a tad bit related to this topic...

Why are there two arteries and only one vein in the umbilical chord? Like, the blood in the arteries - Does the baby extract so much nutriment from that blood that only one vein is needed?

But then I'm thinking that the vein still has to carry all of the baby's waste. To me it just makes more sense to have 2 of each. Like, shouldn't the volumes of blood be equal?

ronbyrne2005

i think human growth hormaone can create new skeletal muscle cells when injected ,dont know bout cardiac muscle