Abstract

BACKGROUND: Polyamine synthesis or uptake, or both, might be an important event that initiates the adaptive hyperplasia seen in the intestinal remnant after partial small bowel resection. AIM: The ability of an enteral diet supplemented with the ornithine salt: ornithine alpha ketoglutarate (OKG), a precursor for polyamine synthesis, to modulate the adaptive response of the remnant ileum after jejunectomy was evaluated. METHODS: Adult Wistar rats underwent a resection of the proximal 50% of the small intestine. Controls underwent a single transection. The rats were fed intragastrically with a nutritive mixture supplemented either with casein hydrolysate or with OKG (1 g/kg). The isoenergetic and isonitrogeneous diets was given continuously for seven days. RESULTS: Villus and crypt hyperplasia was observed in the remnant ileum compared with transfected controls. OKG supplementation started after resection a further increase in villus height. After resection, OKG supplementation increased significantly the putrescine content and the amount of ornithine decarboxylase mRNA. A twofold to threefold increase of sucrase activity was measured in the resected animals compared with the transected rats. In contrast, the amount of sucrase mRNA was significantly lower in the ileum of the resected rats and OKG supplementation initiated a further drop in the amount of sucrase mRNA without pronounced changes in enzyme activity. CONCLUSIONS: The adaptive hypertrophy seen after resection can be accelerated by supplementing the diet with ornithine (OKG) a precursor of polyamine synthesis. In the remnant ileum, the reduced amount of sucrase mRNA, despite the increased level of sucrase activity, suggests a post-translational control of sucrase expression.