title: Cell kinetic study of murine jejunal crypts during multiple doses per day.
abstract: We studied cell kinetics of mouse jejunal crypts during multiple fractionation using double labeling methods. Mice were irradiated to the total body once a day or twice a day. Fraction size was 2 Gy. Overall time was 1, 3 and 5 days. Labeling index (LI), duration of S phase (Ts) and potential doubling time (Tpot) were assessed next morning following the irradiation schedule. Mice were administered both bromo-deoxyuridine (BrdUrd) and 3H-Thymidine ([3H]dT) with a constant interval. Removed jejunum were stained with immuno-histochemistry and, then, processed for autoradiography. BrdUrd and [3H]dT LIs were the same and were increased up to 5 days despite the fractionation schedule. After 1 day following 2 fx/day, both Ts and Tpot decreased significantly. For 1 fx/day treatment, neither Tpot nor Ts changed. After 5 day following 1 and 2 fx/day, both Ts and Tpots were the same and Tpots were significantly shorter than that obtained from control. It seems that proliferative responses between 1 and 2 fx/day were different.
authors.affiliation: Department of Radiology and Nuclear Medicine, Tohoku University, Sendai, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Abe
authors.forename: J
authors.initials: J
authors.lastname: Takahashi
authors.forename: H
authors.initials: H
authors.lastname: Fukuda
authors.forename: K
authors.initials: K
authors.lastname: Yoshida
mesh_terms: D000818:Animals; D001973:Bromodeoxyuridine; D002455:Cell Division / Q000528:radiation effects; D005260:Female; D007583:Jejunum / Q000166:cytology / Q000528:radiation effects*; D007700:Kinetics; D051379:Mice; D008809:Mice, Inbred C3H; D011879:Radiotherapy Dosage; D013936:Thymidine / Q000378:metabolism
chemical_list: D001973:Bromodeoxyuridine; D013936:Thymidine