STIMULATION OF HEPATIC REGENERATION AFTER PARTIAL-HEPATECTOMY BY INFUSION OF A CYTOSOL EXTRACT FROM REGENERATING DOG LIVER

Abstract

A cytosol liver extract was prepared from adult dog livers and from liver remnants that were regenerating for 1, 2 and 3 days after 72% partial hepatectomy. Given intraportally, the most active of these cytosols did not stimulate proliferation in the livers of normal dogs. Infused during a 6 h period into the portal vein of test group dogs, the cytosol from 48 and, especially, 72 h regenrating livers augmented the regeneration response ordinarily produced by 44% partial hepatectomy. The effect was delayed. It became identifiable 48 h after infusion and reached a peak at 72 h. Neither augmentation nor significant inhibition of the normal regeneration response was produced by cytosol from normal liver and 24 h regenerating liver or by a 6 h infusion of insulin. The amplification effect of active cytosol was equivocal when the infusions were given i.v. and was not demonstrable at all by i.v. route. There are apparently growth control factors in regenerating liver but the nature or physiologic significance of the factor or factors was not clarified.