COMPARISON BETWEEN THE NATURAL POSTNATAL MATURATION AND THE SPERMINE-INDUCED MATURATION OF THE RAT INTESTINE

In the suckling rats, orally provided spermine induced structural and biochemical changes in the intestine, which are characteristics of the postnatal maturation. This induced maturation was compared to that oc curring spontaneously. Eight mu mol spermine were administered orally once a day, for one or three days, to suckling rats which were Il days old at the beginning of the experiment. The animals were killed 0, 2, 4, 6, 8, 10 hours or 3 days after the first treatment. Control rats f rom the same litter were treated in the same way but received only the vehicle. In order to complete the study of the naturally occurring ma turation, another group of rats was killed when they were 12, 13, 15, IG, 17, 18, 19, 20, 21 or 30 days old. Animal and intestine weights we re measured. Disaccharidase specific activity, and protein, DNA and RN A contents were estimated in the small intestine. Histological and ult rastructural aspects of the intestinal mucosa were examined. For all t hese parameters, the maturation induced by spermine ingestion appeared close to that occurring naturally at weaning. Consequently, dietary s permine induces all the morphological and biochemical modifications ch aracterizing the intestinal postnatal maturation in the suckling rat s uggesting a role of the polyamines in the naturally occurring processe s.