[Change on the cell proliferation kinetics of the central and peripheral regions of DMBA induced hamster tongue cancer following irradiation].
Cellular changes on the vascular and peripheral sides of DMBA-induced cancer of the tongue in hamsters, were assessed by [3H] thymidine cellular labelling, one and three days after irradiation by 60Co-gamma ray at 20 Gy. The results obtained were as follows: 1) Initial labelling index (L.I.) was high on the vascular side and low on the peripheral side before irradiation. The L.I. on the day following irradiation was decreased was decreased for the whole tumor. The vascular side demonstrated a decrease of about 43% while there were no changes on the peripheral side. This tendency was still observed 3 days after irradiation. 2) Mitosis index (M.I.) were high on the vascular side, and low on the peripheral side before irradiation. On the following day, and three days after irradiation the M.I. was decreased totally, although the decrease was only slight on the vascular side. On the peripheral side, in contrast, the M.I. was increased to about two-fold. 3) There was no difference in the time of cellular rotation (Tc), between vascular and peripheral sides before irradiation, but the Tc on the following day of irradiation was increased by about 3 on both the vascular and peripheral sides of the tumors. In contrast, at three days after irradiation, it was decreased by about 6.5h. 4) There was no difference in the time of preparation for mitosis (Tg2) between the vascular and peripheral sides before irradiation. It was increased by about 2h on both sides on the day following irradiation, and it was increased by about 3h, 3 days after irradiation. 5) Although there was no difference in the time of mitosis (Tm) between both sides, on the day following irradiation, it was increased by about 1.6 times, and 2.1 times, on the vascular and peripheral sides, respectively. A very similar tendency was observed even 3 days after irradiation. 6) There was no difference in the time of DNA synthesis (Ts) between the vascular and peripheral sides of the tumors before irradiation, or at one, or three days after irradiation. 7) Although there was no difference in the time of preparation for synthesis (Tg1), between both sides before irradiation, or on the day following irradiation, it showed a marked decrease of about 90% on both sides of the tumors 3 days after irradiation.
Inoue
T
T
Nasu
M
M
Kai
Y
Y
Furumoto
K
K
D015127:9,10-Dimethyl-1,2-benzanthracene; D000818:Animals; D006224:Cricetinae; D008938:Mitosis / Q000528:radiation effects; D011882:Radiotherapy, High-Energy; D014062:Tongue Neoplasms / Q000098:blood supply / Q000139:chemically induced* / Q000473:pathology
D015127:9,10-Dimethyl-1,2-benzanthracene