Open AccessAge‐related changes in the cell proliferation of ATPC + mouse ascites tumour
Author(s) -
ViolaMagni M. P.,
Biagetti M.
Publication year - 1991
Publication title -
cell proliferation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.647
H-Index - 74
eISSN - 1365-2184
pISSN - 0960-7722
DOI - 10.1111/j.1365-2184.1991.tb01184.x
Subject(s) - thymidine , ascites , cell growth , cell cycle , biology , cell , in vivo , mitosis , thymine , endocrinology , medicine , andrology , in vitro , biochemistry , microbiology and biotechnology , genetics , dna
. The growth of ATPC + , an ascites tumour derived from a spontaneous mammary carcinoma in BALB/c + mice, was studied at different ages. It was observed that the number of cells increases rapidly during the first 5 days after implantation. Thereafter, the cell number increases more slowly, reaching a plateau after 8 days. This slowing‐down is not due to a reduction in the growth fraction but to a lengthening of the cell cycle. Between 5 and 8 days the duration of all phases increases, including the S phase, which increases from 5·2 h in 5‐day tumours to 8·2 h in 8‐day tumours. In 12‐day tumours both the cell cycle and S phase are only slightly longer than in 8‐day tumours whereas the growth fraction is reduced. The slowing‐down of cell growth can be attributed to growth fraction reduction rather than cell loss, which is maximal in the 5‐day tumour. At this age the time course of the percent labelled cells and of the number of grains/nucleus suggests reutilization of [ 3 H]‐thymidine. Incorporation of [ 3 H]‐thymidine/cell decreases sharply in 12‐day tumours due to a reduced availability of thymidine, which is degraded to thymine in the in vivo ascitic fluid faster than in 8‐day tumours. This indicates an age‐related change in the ascitic fluid composition.