It is not completely understood how a liver can
grow back to its original size and function.
The liver has a remarkable capacity to
regenerate after injury and to adjust its size to
match its host. Within a week after partial
hepatectomy (surgical removal of all or part of
the liver), which means normally the surgical
removal of two-thirds of the liver, hepatic
(liver) mass is back essentially to what it was
prior to surgery. This observation has prompted
considerable research into the mechanisms
responsible for hepatic regeneration.
The Dynamics of Liver Regeneration
Researchers found that partial hepatectomy
leads to proliferation (or growth) of all
populations of cells within the liver,
including hepatocytes, biliary epithelial cells
and endothelial cells. DNA synthesis is initiated
(or started) in these cells within 10 to 12 hours
after surgery and essentially ceases in about 3
days. It appears that hepatocytes (fragments of
the liver) have a practically unlimited
capacity for proliferation (growth).
What stimulates the Regeneration?
Hepatic regeneration is triggered (or started) by
the appearance of circulating mitogenic
factors. >As might be expected, liver
regeneration seems to be supported by a group of
mitogens and growth factors acting in concert on
several cell types. Some of the major and
well-studied players that act together in this
Hepatocyte growth factor
Epidermal growth factor
The processes and signals involved in shutting
down the regenerative response are less well
studied than those that stimulate it.
Click Here to return to the search form.