AJP - Regulatory, Integrative and Comparative Physiology, Vol 248, Issue 4 459-R463, Copyright © 1985 by American Physiological Society
Oral stimulation alters digestion of intragastric oil meals in rats
I. Ramirez
Rats were fed corn oil by gastric catheter, and plasma levels of
triglycerides were measured 1-6 h later. In previous studies intragastric
feeding of oil resulted in a more rapid rise in plasma triglycerides,
followed by a more rapid fall, than oral feeding of the same amount of oil.
In the present study administration of a small amount of oil or saccharin
to the mouths of rats immediately before intragastric feeding prolonged the
elevation in blood triglycerides 4 h later. This latter effect appeared
only in rats having previous experience with oil paired with the taste.
Oral stimulation with saccharin also increased the amount of fat remaining
in the stomach 1 h after the intragastric meal. The amount of free fatty
acids remaining in the stomach 1 h after intragastric feeding was not
significantly influenced by oral stimulation, suggesting that lingual
lipase is not responsible for the observed effects. These findings
demonstrate that a taste which has been paired with fat intake can acquire
the ability to influence the digestion of fat.
