Tohru Kawasaki

Anticancer effects of a chinese Herbal medicine, Juzen-taiho-to, in combination with or without 5-fluorouracil derivative on DNA-synthesizing enzymes in 1,2-dimethylhydrazine induced colonic cancer in rats

Juzen-taiho-to (JTT; [Shi-quan-da-bu-tang], a Japanese modified Chinese herbal prescription) in combination with an anticancer drug UFT (5-fluorouracil derivative) prevented the body weight loss and the induction of the colonic cancer in rats treated with a chemical carcinogen 1,2-dimethylhydrazine (DMH), and suppressed markedly the activity of thymidylate synthetase (TS) involved in the de novo pathway of pyrimidine synthesis in colonic cancer induced by DMH.

Effects of estrogen and prolactin on thymidine kinase isozyme activities in DMBA-induced rat mammary tumor.

Effects of prolactin or estrogen on the activity of the pyrimidine salvage pathway enzyme thymidine kinase (TK) in 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary tumors were investigated in ovariectomized rats. Prolactin induced by perphenazine administration significantly enhanced the activities of total TK or its isozyme in the tumors. This specific TK isozyme separated by DEAE-cellulose column chromatography was suggested to be involved in DNA synthesis because it was not affected by dCTP. Its Mr was estimated to be approx. 100 000 by high-performance liquid chromatography. In contrast, estrogen alone did not raise the activity of the specific TK isozyme in the tumors.

Effect of Ba-wei-di-huang-wan (Hachimi-jio-gan) on thymidine kinase and its isozyme activities in the prostate gland in rats

Ba-wei-di-huang-wan (Hachimi-jio-gan, TJ-7) has been frequently used for the treatment of sterilitas virilis, prostatic disorders, etc. The hormonal effects of TJ-7 were studied using thymidine kinase (TK), an enzyme that catalyzes the phosphorylation of thymidine via the pyrimidine salvage pathway. TK isozyme activity increases in rapidly proliferating tissues. TJ-7 may act as a weak androgen and enhance prostatic TK and in particular, a specific TK isozyme activity, and also as an anti-androgen and reduce prostatic TK activity in the presence of androgen in immature rats.

Effects of ACTH or hCG on corticosterone and progesterone secretion from adrenal glands of the rats at various ages

Effects of ACTH or hCG on the secretion of corticosterone (CB) and progesterone (PRG) from adrenal glands of the female rats at various ages were studied. In in vitro experiment, adrenal gland cells were isolated from fetal, neonatal, immature and adult rats by the method described by us before and were incubated in MEM. We chose to designate the hormones in the medium as hormone secretion. In in vivo experiment, hormones in the serum were determined. In vitro experiment, in which ACTH was added to the medium, indicated that CB was low in the media containing the cells from fetal and neonatal glands compared to those from immature and adult. PRG was elevated by ACTH addition at all of the ages. hCG addition had no effects on both CB and PRG in the media of immature and adult rats. In vivo experiment, in which ACTH was injected s.c., indicated that the response of serum PRG was slightly earlier than the CB response and peaked with a subsequent decline in immature rats. The results suggest that adrenal gland responds to ACTH from fetal age and secrets PRG, but little of CB in fetal age.