The effect of increased motility on absorption from the canine colon

The absorption of water and electrolytes and intraluminal pressure were measured from Thirty-Vella loops in 4 dogs under basal conditions and during electrical stimulation of the colonic smooth muscle. Pulse wave electrical stimulation via serosal silver/silver chloride electrodes gave rise to significant increases in both intraluminal pressure and percentage motility. Absorption of water, sodium and chloride was significantly increased during stimulation but the transport of ammonia, bicarbonate and potassium was not significantly affected. It is suggested that motility changes result in altered absorption irrespective of transit time.