Two-month glucocorticoid treatment increases proliferation in the stomach and large intestine of rats.
OBJECTIVE
It has been shown that acute or short-term treatments with glucocorticoids lead to a marked decrease in proliferation in the stomach and large intestine. The effects of more prolonged glucocorticoid treatment on cell renewal in these organs are not known. The present work was therefore undertaken to examine the proliferative activity in the stomach and colon during 2 months of glucocorticoid treatment in comparison with shorter treatments.


METHODS
Rats were treated with either the glucocorticoid triamcinolone acetonide or vehicle for 63, 33 or 3 days. Proliferation was assessed in the glandular epithelium of the fundal part of the stomach and in the epithelium of the colonic crypts using three criteria: the mitotic index; the bromodeoxyuridine labelling index, and the proliferating cell nuclear antigen-labelling index (percentage of mitotic or labelled cells).


RESULTS
Treatment with glucocorticoid for 63 days resulted in a very significant increase in all proliferative parameters tested in the gastric mucosa and the colonic crypts. On the contrary, treatments with glucocorticoid for 3 or 33 days had a marked inhibitory influence on proliferation in these tissues.


CONCLUSIONS
As opposed to treatments for 3 or 33 days, glucocorticoid treatment for 2 months leads to an increase in the number of cycling cells in the gastric and colonic mucosae.
Gunin
A G
AG
Department of Histology, Medical Institute Chuvash State University, Cheboksary, Russia. drgunin@yahoo.com
Nikolaev
D V
DV
D000704:Analysis of Variance; D000818:Animals; D002455:Cell Division / Q000187:drug effects; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects; D005938:Glucocorticoids / Q000494:pharmacology*; D007420:Intestine, Large / Q000187:drug effects*; D008297:Male; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis; D051381:Rats; D013270:Stomach / Q000187:drug effects*; D013997:Time Factors; D014222:Triamcinolone Acetonide / Q000494:pharmacology*
D005938:Glucocorticoids; D018809:Proliferating Cell Nuclear Antigen; D014222:Triamcinolone Acetonide