Alkaline phosphatase and disaccharidase activities in the rat intestine from birth to weaning. I. Effect of diet on enzyme development

Publisher Website
Google Scholar
Abstract
Intestinal alkaline phosphatase and disaccharidase activities were determined along the gut in suckling and weaning rats. In normal animals, specific changes occur during this period that concern the enzyme nature, the level of enzymatic activity, and the location of maximum activity in the gut. An attempt was made to influence these intestinal enzymatic properties by changing the nature of food. 1) Lactose-free food (Hyprovit) was used as a weaning inducer in two groups of rats of different age. Of the younger rats (8 days old), the majority died. No change in the levels of the existing enzymes could be observed after 72 hr on Hyprovit and no sucrase activity appeared. 2) The second group (15-day-old rats) adapted well to this artificial feeding, which induced the enzymatic changes associated with weaning 2 days earlier. 3) Lactose-rich food (goat milk, 4.6% lactose) was given to a third group of rats (17 days old) for a period of 5 days. This diet neither prevented nor delayed the natural decrease of the ileal enzymes including lactase. 4) The same diet (goat milk) was given to young adult rats for 5 days. Both jejunal lactase and duodenal phosphatase increased. As sucrase, but not maltase, appeared enhanced also, we explained these results as the sum of two different factors; one of a dietetic nature, lactose acting as a substrate inducer enzyme on lactase, and the second as one of hormonal nature, provoked by the stress of the artificial feeding and responsible for the higher levels of jejunal sucrase and duodenal alkaline phosphatase. It was concluded that from a certain period (approximately the 15th day of life), both diet and hormones are involved in the intestinal enzymatic activities.