Changes of substance P and somatostatin contents in the gastrointestinal tract of streptozotocin diabetic rats.

Substance P and somatostatin contents were measured in the gastrointestinal tract of streptozotocin diabetic rats, 1 month after streptozotocin administration (60 mg/kg), and of age-matched controls with radioimmunoassay. Substance P and somatostatin contents were statistically increased in the extrafundus of the diabetic stomach, but not in the diabetic fundus. Substance P was significantly decreased in the diabetic ileum and caecum. Similarly, somatostatin was decreased in the diabetic caecum. Contrarily, slight increase of somatostatin contents in the diabetic duodenum, jejunum and proximal colon was not statistically significant.