Abstract
Intraperitoneal administration of ginseng extract (fraction 3 or 4) to rat was found to increase the rate of synthesis of serum proteins such as albumin and γ-globulin. The incorporation rate of 3H-leucine into serum proteins was significantly increased 4 hr after the injection of fraction 3. The increased rate of protein synthesis reached a maximum about 8-12 hr after the administration and 46-49% increase in the rate of serum protein synthesis was observed. It was confirmed by immunochemical precipitation reaction that the increase in serum protein synthesis was due to the stimulation of albumin and γ-globulin synthesis. The rate declined to the control level at 20 hr following ginseng extract treatment. These observations are similar to the effect of cortisone on the liver. Although the mechanism of this increase in the rate of serum protein synthesis by ginseng extract is not known, some differences were observed in effects between fraction 4 and cortisone as follows. Induction of tryptophan pyrrolase and tyrosine transaminase, which is observed with cortisone, did not occur by fraction 4 administration. These results suggest that the observed effect of ginseng extract would not be due to the elevated concentration of adrenocortical steroids. From this point of view, this stimulating factor, which we term "prostisol"(protein synthesis stimulating factor), is active to RNA and protein syntheses when administered in vivo.
