泌尿器腫瘍と酵素 1.実験的ラット前立腺腫瘍におけるLDH,ALP活性,LDH isozymeの変動ならびに諸種ホルモンのこれらに及ぼす影響について

Abstract

A local injection of 20-methylcholanthrene (20 MC) was performed into the dorsolateral lobe of the prostatic gland of male Wistar strain rats, weighed about 100 g. Such treated rats were divided into 4 groups and were combinedly given none or subcutaneous injection of either one of estradiol benzoate (Eb), testosterone propionate (TP) or thyriod powder (Thy). Rats given neither 20 MC nor hormones reserved as the control. The prostatic and serum LDH activity, LDH isozyme and ALP activity were determined along with the lapse of time for a period of 11 months. The results obtained are summarized as follows. (1) The LDH activity of the prostatic tissue sho w ed a tendency of increase with advancing of age. It slightly decreased in the rats given 20 MC only and 20 MC with Eb, while it slightly increased in the rats given 20 MC with Tp and 20 MC with Thy. The serum LDH activity, however, showed a tendency of increase in control group as far as the value obtained 11 months after the start of the experiment was concerned. It also showed an increase in the 20 MC simple-treated group and a decrease in the groups given 20 MC combined with TP or Eb. (2) The LDH isozyme pattern of the prostatic tissue showed a decrease of M-type and an increase of H-type with advancing of age. Increase of M-type was observed in the 20 MC simple-treated and 20 MC with Tp treated groups, but decrease of M-type was seen in the 20 MC with Eb treated group. The serum LDH isozyme also showed ageing changes characterized by an increase of M-type and decreases of H-type and III-component. In rats given 20 MC with Thy M-type was higher than the others in general. (3) The ALP activity of the prostatic tissue w as not affected with ageing. It slightly decreased in the group 20 MC with Eb, but no noticeable change was observed in both of groups given 20 MC along with Tp or Thy. The serum ALP activity showed an increase in the 20 MC simple-treated group and a decrease in both of the groups given with combination of Eb or Tp.