Open AccessFASTING AND REFEEDING: CELL KINETIC RESPONSE OF JEJUNUM, ILEUM AND COLON
Author(s) -
Hagemann Ronald F.,
Stragand James J.
Publication year - 1977
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.1365-2184.1977.tb00278.x
Subject(s) - crypt , ileum , jejunum , medicine , endocrinology , cell cycle , biology , chemistry , cancer
Following a period of fasting, feeding a normal diet results in a burst of DNA synthesis in the crypts of the colonic epithelium. This is due largely to a prompt entry of cells, blocked in G 1 , into S. Peak levels of S cellularity exceed 4 times the fasting, and 2 times the normal fed, control values. Refeeding a low residue diet (soluble casein, glucose and corn oil) results in a return to control levels of proliferative activity, but no hyperplasia. However, in jejunum and ileum, refeeding is followed by a return to near control levels of proliferation with only a slight overshoot in S phase cellularity. During the fasting period, the ileal crypt proliferative compartment (P c ‐zone) and total crypt cellularity decline significantly. These changes are accompanied by an increase in the total cycle time, due to an equivalent lengthening of the G 1 and S phases. Following refeeding, there is a reduction in the cycle time and a gradual return to the control values for the P c ‐zone size and cellularity. In the colon, fasting has no effect on the P c ‐zone size or total crypt cellularity. There is an approximate doubling of the cycle time due solely to an increase in G 1 . Following refeeding there is an increase in the P c ‐zone size and crypt cellularity and a marked shortening of the cycle time. Evidence that a G 1 cycle blockade is induced in the colon by fasting is given by a lengthening of the G 1 period and by stathmokinetic studies employing vincristine.