WHEN DOGS or rats are subjected to partial hepatectomy at repeated intervals, the remaining liver increases in bulk to replace the deficit. If one-fifth to three-fourths of a dog's liver is removed, the remaining part regenerates completely in from six to eight weeks. Similarly a rat liver will resume its previous size in 14 to 16 days following partial removal. It often happens that the restored liver weighs more than the original organ. According to Markowitz,1 the remaining part of the liver responds as rapidly and completely after the second or third partial hepatectomy as after the first.
The cause of hepatic restoration may possibly be the relatively increased blood supply, since after operation blood from the portal vein and the hepatic artery traverses a smaller mass of tissue. In a paper on the relation of portal blood flow to liver maintenance, Rous and Larimore2 pointed out the