Effect of acetic acid and oral glutamine on crypt cell proliferation. 5-BrdU incorporation into proliferating jejunal and ileal crypt cells was detected with a goat anti-BrdU antibody. The representative sections (on the right side) demonstrate that cell proliferation decreased following AA-damage compared to control animals. Following administration of oral glutamine, AA-rats demonstrated a marked increase in a number of proliferating cells compared to AA non-treated animals. Values are mean ± SEM. CONTR-control; AA- acetic acid; GLN- glutamine. * P < 0.05 vs CONTR rats, † P < 0.05 AA-GLN vs AA rats.