Developmental behavior of N,N'-dimethylnitrosourea-induced brain gliomas and influence of a stab wound in adult rats.
The developmental behavior of rat brain gliomas induced by weekly injections of N,N'-dimethylnitrosourea (DMNU) from the age of three weeks was studied. In addition, the influence of the repair process of a stab wound on tumor induction by DMNU was examined. From seven weeks after the first injection of DMNU, a loss of subependymal cells appeared along with a decrease in labeling indices in flash labeling with 3H-thymidine. From twenty weeks, gliomas began to appear. Their distribution was much denser in the vicinity of the depleted subependymal layer than in the periphery of the cerebral hemisphere, and corresponded to the distribution of labeled cells in the normal adult brain. Microtumors composed of less mature glial cells grew to histologically mature gliomas with the lapse of time. No effect of the stab wound was observed on the incidence, distribution or latency period of glioma development. From these results, it was concluded that DMNU-induced gliomas develop in close relation to cellular differentiation of target cells. It was assumed that mature gliomas are derived from less mature glial cells in the glioblastic (spongioblastic) stage or migrating neuroglias remaining in adult rat brains.
D000818:Animals; D001930:Brain Injuries / Q000150:complications*; D001932:Brain Neoplasms / Q000139:chemically induced / Q000209:etiology / Q000473:pathology*; D002455:Cell Division; D005260:Female; D005910:Glioma / Q000139:chemically induced / Q000209:etiology / Q000473:pathology*; D008297:Male; D008770:Methylnitrosourea / Q000031:analogs & derivatives*; D009607:Nitrosourea Compounds; D051381:Rats; D014950:Wounds, Penetrating / Q000150:complications
D009607:Nitrosourea Compounds; C001049:N,N'-dimethylnitrosourea; D008770:Methylnitrosourea