抄録
In vivo administration of extract of Panax ginseng C. A. Meyer (ginseng root) increased incorporation rates of labeled orotic acid into rapidlysynthesized liver nuclear RNA in 4 hr after treatment on an intact rat. The incorporation rates were dependent directly on the amount of purification substance (prostisol) administered to a rat, and the maximum increase was shown in 4 hr after the intraperitoneal administration and returned almost to the control level in 24 hr after the treatment. In the incorporation rates of labeled precursor, interphase RNA isolated from phenol-treated nuclei was more stimulated significantly by prostisol than nuclear sap RNA. Sedimentation profile by sucrose density gradient of rapidly labeled nuclear RNA from the prostisol-treated rat liver showed the stimulation in the 23 S to 7 S regions which has a peak at 10S region.
It was shown that a single intraperitoneal injection of prostisol increased activity of RNA. polymerase (EC 2.7. 7.6), assayed in vitro, of deoxycholate-lysed nuclei of rat liver. The maximum increase of the enzyme activity was found in 2 hr after prostisol-treatment with a lag period of 30 min. The increase in activity of the polymerase due to prostisol did not disappear even when puromycin greatly inhibited synthesis of proteins.
Prostisol stimulated incorporation of labeled precursor into cytoplasmic polyribosomal RNA, and the maximum increase was shown in 5.5 hr after the administration. It was observed that heavy polyribosome (over octamer) content in the purified polyribosome from the prostisol-treated liver increased significantly in 6 hr in total U. V. absorbance obtained by sucrose density gradient centrifugation. On the other hand, at the peaks of monomer, dimer, trimer and tetramer, their contents were decreased by prostisol at this time. The same tendency was indicated in postmitochondrial supernatant profile by sucrose density gradient centrifugation, and prostisol enhanced obviously incorporation rate of labeled precursor into polyribosomal RNA. In an amino acid incorporation system in vitro, stimulatory activities of microsomes and polyribosomes from the treated-rat liver (in 6 hr after treatment) are more active by 85 and 67% than those from a normal liver, respectively.
Intraperitoneal administration of prostisol was shown to cause an increase in the rate of synthesis of serum protein such as albumin and γ-globulin. Incorporation rate of 3H-leucine into serum proteins was significantly increased in 4 hr and increased rate reached the maximum (44-47%) in about 8-10 hr after administration. It was confirmed by immunochemical precipitation reaction that the increase in serum protein synthesis was due to stimulation of albumin and γ-globulin synthesis.
