Ethylene diamine tetraacetic acid-induced colonic crypt cell proliferation in rats.
OBJECTIVE
To investigate the effect of ethylene diamine tetraacetic acid (EDTA) on proliferation of rat colonic cells.


METHODS
EDTA was administered into Wistar rats, carcinogenesis induced by 1,2-dimethylhydrazine (DMH) in rats was studied with immunohistochemistry.


RESULTS
Marked regional differences in cell proliferation were found in all groups. In EDTA-treated animals, total labelling indexes in both proximal (10.00 +/- 0.44 vs 7.20 +/- 0.45) and distal (11.05 +/- 0.45 vs 8.65 +/- 0.34) colon and proliferative zone size (21.67 +/- 1.13 vs 16.75 +/- 1.45, 27.73 +/- 1.46 vs 21.74 +/- 1.07) were significantly higher than that in normal controls (P<0.05) and lower than that in DMH group (10.00 +/- 0.44 vs 11.54 +/- 0.45, 11.05 +/- 0.45 vs 13.13 +/- 0.46, 21.67 +/- 1.13 vs 35.52 +/- 1.58, 27.73 +/- 1.46 vs 39.61 +/- 1.32, P<0.05). Cumulative frequency distributions showed a shift of the EDTA distal curve to the right (P<0.05) while the EDTA proximal curve did not change compared to normal controls. Despite the changes of proliferative parameters, tumours did not develop in EDTA treated animals.


CONCLUSIONS
Hyperproliferation appears to be more easily induced by EDTA in distal colon than in proximal colon. Hyperproliferation may need to exceed a threshold to develop colonic tumours. EDTA may work as a co-factor in colonic tumorigenesis.
Ma
Qing-Yong
QY
Department of Surgery, First Hospital of Xi'an Jiaotong University, Xi'an 710061, Shaanxi Province, China. qyma0@163.com
Williamson
Kate E
KE
Rowlands
Brian J
BJ
D000230:Adenocarcinoma / Q000139:chemically induced / Q000473:pathology; D000236:Adenoma / Q000139:chemically induced* / Q000473:pathology; D000818:Animals; D001973:Bromodeoxyuridine; D002455:Cell Division / Q000187:drug effects; D002614:Chelating Agents / Q000494:pharmacology*; D003106:Colon / Q000166:cytology* / Q000187:drug effects*; D015179:Colorectal Neoplasms / Q000139:chemically induced* / Q000473:pathology; D004195:Disease Models, Animal; D004492:Edetic Acid / Q000494:pharmacology*; D008297:Male; D051381:Rats; D017208:Rats, Wistar
D002614:Chelating Agents; D004492:Edetic Acid; D001973:Bromodeoxyuridine