The absorption of vitamin B12 after subtotal pancreatectomy in the rat.

Subtotal pancreatectomy in the rat was performed by a new method. Except for a small remnant along the splenal hilus, the gland was completely removed. Exocrine pancreatic insufficiency was confirmed by fat and nitrogen malabsorption. A moderate diabetes mellitus was seen. Insulin substitution or diet restriction was unnecessary. The absorption of vitamin B12 after oral administration of 10 ng 57CoB12 was 5.0 +/- 0.2 (ng 57CoB12 +/- S.E.M.) in unoperated rats and 5.1 +/- 0.1 in pancreatectomized rats (p greater than 0.5). Pancreatic extract (PE) (100 mg) increased the absorption of 57CoB12 in unoperated rats (p less than 0.01), but not in pancreatectomized rats (p greater than 0.2). PE (300 mg) reduced the absorption in unoperated rats (p less than 0.01). The results indicate that an optimal amount of pancreatic secretion may stimulate the absorption of vitamin B12.