Abstract
The fresh weight of jejunal mucosa was significantly lower in specific pathogen-free (SPF) than in conventional rats. An almost two-fold higher activity of mucosal alkaline phosphatase, ATPase, and maltase was observed in the duodenum and jejunum of the SPF rats. The SPF rats also had a significantly higher glucuronide synthesizing activity in tissue slices from the duodenum, where UDP glucuronyltransferase activity was also slightly higher than in conventional controls. The results suggest that the microflora is of importance in the regulation of enzyme levels in the small intestinal mucosa of the rat.