AJP - Gastrointestinal and Liver Physiology, Vol 250, Issue 3 302-G308, Copyright © 1986 by American Physiological Society
Colonic formation of soft feces in rabbits: a role for endogenous prostaglandins
M. Pairet, T. Bouyssou and Y. Ruckebusch
Rabbits produce hard and soft feces in a circadian rhythm. The motor
activity of the haustrated proximal colon is inhibited during the formation
of soft feces, whereas the spiking activity of the distal colon is
stimulated. A potential role for endogenous prostaglandins (PG) in the
control of the soft-feces elaboration by the rabbit colon was investigated
in conscious animals by using PGE2 and PGF2 alpha and by inhibiting them
with indomethacin. The infusion of both PGE2 and PGF2 alpha induced typical
electromechanical events consisting of inhibition of the proximal and
stimulation of the distal colon and was followed by soft-pellet defecation.
Rabbits accustomed to be fed twice daily produced soft feces at fixed
intervals of 252 +/- 32 min after the evening meal, with a soft-to-hard
feces ratio of 1.45. After indomethacin treatment, this ratio was
significantly (P less than 0.01) reduced to 0.92. These results are
consistent with the concept that endogenous prostaglandins play a major
role in the motor function involved in soft-feces formation by the rabbit.
