title: The decay of autoradiographic grain number over crypt base columnar cells in murine ileum as a measure of their generation time.
abstract: The decay in the number of grains over [3H]-thymidine labelled crypt base columnar cells (BCC) in autoradiographs of the ileum of BDF1 mice has been studied. The results revealed that using the conventional grain count halving (GCH) method it is possible to obtain an estimation of the generation time (Tc) of the proliferative BCC cells in the Paneth cell zone (PC-zone) of 18.8 +/- 0.74 h. This lies within the range obtained by the percent labelled mitoses (PLM) method, but is shorter than most values obtained by stathmokinetic methods. The present data show no evidence for a shortening of the cell cycle 3 days after irradiation (8 Gy) which is contrary to some earlier observations. Some reasons for this discrepancy are discussed. The comparatively high labelling index of the BCC allows a larger amount of data to be easily collected, compared with the PLM technique, and correction factors which take into account the complicated shape of the bottom of the crypt are not required.
authors.affiliation: Department of Pathophysiology, Institute of Rheumatology, Warsaw, Poland.
authors.forename: S
authors.initials: S
authors.lastname: Chwalinski
authors.forename: C S
authors.initials: CS
authors.lastname: Potten
mesh_terms: D000818:Animals; D001345:Autoradiography; D002455:Cell Division; D002465:Cell Movement; D007082:Ileum / Q000166:cytology*; D007413:Intestinal Mucosa / Q000166:cytology*; D008297:Male; D051379:Mice