AJP - Gastrointestinal and Liver Physiology, Vol 241, Issue 3 259-G263, Copyright © 1981 by American Physiological Society
Adaptation of intestinal muscle in continuity after jejunoileal bypass in the rat
P. R. Nemeth, D. J. Kwee and N. W. Weisbrodt
Functional and structural adaptations of the intestine that remained in
continuity after jejunoileal bypass [the in-continuity (IC) segment] were
characterized in the rat. Three days after bypass, transit was rapid in fed
rats, but, by 35 days, transit had slowed to mimic that seen in the intact
intestine of control animals. In fasted rats, transit was as rapid as in
the fed animals at 3 days after bypass; however, in fasted rats, transit
did not slow when tested up to 35 days after operation. Transit in animals
at 3, 14, and 35 days after sham operation was not different from control.
Mucosal weights in the proximal and distal portions of the IC segment were
increased at 3, 14, and 35 days after bypass. The wet weights and protein
contents of the muscle and serosal layers of both portions of the IC
segment were increased at 35 days. These findings support the hypothesis
that the adaptation seen in the IC segment after bypass involves changes in
function and structure of the intestinal smooth muscle as well as the
intestinal mucosa.
