Why do some internal organs regenerate?

Question

I have been reading about the human liver and zebra fish heart muscle having the ability to regenerate. It seems to me that these organs have very little chance to become damaged or worn out. At the very least their chances of being damaged are comparable to other internal organs. So why those particular organs have the regenerative capability?

Answer 1

The liver is actually the primary filter for many toxins that enter the body and for many of the toxins the body produces. For example, warfarin and tylenol are two medications that are primarily metabolized by the liver. Alcohol is another common "drug" metabolized by the liver. Viruses, such as hepatitis (A,B,C,D and E), bacteria, and parasites can all damage the liver. The liver can suffer loss of blood flow in ischemic hepatitis, and can suffer deposition of iron and copper in conditions such as Wison's disease and hemochromatosis. The ability of the liver to regenerate is extremely important in these cases. Why other organs cannot do this is the subject of a lot of research. Hepatocytes are brilliantly designed to regenerate under certain conditions and under other conditions to create scarring, known as fibrosis. This has to do with the function of these cells on the molecular level.