Morphometric analysis of the endocrine pancreas in streptozotocin-diabetic rats kept on different dietary regimens

The effects of different diets on the endocrine pancreas of streptozotocin-diabetic rats were investigated by morphometry. Three dietary regimens were used over a period of 43 weeks: standard diet (SD), low carbohydrate-high protein diet (LC-HP), and low carbohydrate-high fat diet (LC-HF). Nondiabetic controls received standard diet. Volume density of the total endocrine tissue was significantly reduced in streptozotocin-diabetic rats kept on standard diet as compared to control rats. This reduction of endocrine tissue was significantly less in rats kept on LC-HP diet, whereas diabetic rats kept on LC-HF did not differ from diabetic rats on standard diet. In streptozotocin-diabetic rats volume density of B cells was drastically reduced, whereas volume densities of A, D and PP cells did not differ from nondiabetic controls. This decrease of B cells was partially prevented by LC-HP diet, but not by LC-HF diet. In nondiabetic control rats as in diabetic rats on standard diet most of the islets of Langerhans sized 500-6000 microns2. In contrast, diabetic rats on LC-HP diet revealed more endocrine tissue sized from 50 to 560 microns2 consisting of two to four endocrine cells, single cells, and small islets. The results suggest that LC-HP diet may initiate reparation processes in the endocrine pancreas of streptozotocin-diabetic rats.