Intragastric cannulation procedures and rats' food intake and body weight maintenance

Effects upon food and water intakes and body weight maintenance of two procedures for preparing rats with chronic intragastric cannulae were examined. A transient aphagia and rapid weight loss followed installation of the classic nasopharyngeal cannula. Growth was resumed after about a week, but subsequent food and water intakes were chronically depressed in comparison to sham operated animals of the same age. Body weight was also chronically subnormal. The response of these animals to caloric dilution of the diet was, however, normal. In contrast to the nasopharyngeal procedure, a method involving direct cannulation of the stomach wall did not lead to either behavioral or weight regulatory deficits and is therefore recommended.