title: The response of murine intestinal crypts to short-range promethium-147 beta irradiation: deductions concerning clonogenic cell numbers and positions.
abstract: An exteriorized loop of mouse intestine was exposed to 147Pm low-energy electrons, where the dose rate decreased by a factor of 5 from the base of the crypt to the top of the proliferative zone. A crypt survival curve was obtained, expressed in terms of exposure time. The shape of the curve was interpreted in terms of survival parameters for colony-forming cells (clonogens) derived using 137Cs gamma rays and the depth-dose curve measured for 147Pm electrons. It is concluded that the shape of the crypt survival curve using 147Pm electrons is inconsistent with the notion of either the presence of a large number of clonogens or a small number near the top of the proliferative zone. A computer fitting procedure showed that the best agreement between predicted and observed curves was achieved with 2.7 +/- 0.5 clonogens at cell position 5.6 +/- 0.6, in the putative stem-cell zone.
authors.affiliation: Paterson Institute for Cancer Research, Christie Hospital, Manchester, United Kingdom.
authors.forename: J H
authors.initials: JH
authors.lastname: Hendry
authors.forename: C S
authors.initials: CS
authors.lastname: Potten
authors.forename: A
authors.initials: A
authors.lastname: Ghafoor
authors.forename: J V
authors.initials: JV
authors.lastname: Moore
authors.forename: S A
authors.initials: SA
authors.lastname: Roberts
authors.forename: P C
authors.initials: PC
authors.lastname: Williams
mesh_terms: D000818:Animals; D001610:Beta Particles; D002470:Cell Survival / Q000528:radiation effects; D003114:Colony-Forming Units Assay; D005260:Female; D007421:Intestine, Small / Q000528:radiation effects*; D051379:Mice; D011399:Promethium
chemical_list: D011399:Promethium