[Pancreatic islets, plasma glucagon and renal calcification in rats fed various diets. Results of a pilot study (author's transl)].

Rats fed abnormally composed isocaloric diets during 21 days (low magnesium, atherogenous, high in proteins or carbohydrates) develop a mean increase in total number of pancreatic A cells, a significant increase of A/B ratio (atherogenous), and hyperglucagonemia in most of the groups under study. Histologic examination reveals calcification most marked in animals under low magnesium and atherogenous diets. They are only scarce following high protein diet; a normal or carbohydrate rich diet nullifies this phenomenon. Independent of the morphologic and functional state of the islets, supplementation by argining and histidine of normal chow is followed by a certain degree of renal calcification. Lowered urinary magnesium and calcium and elevated urinary sodium and phosphate together with a tendency toward hypercalcemia point to stimulation of parathyroids during malnutrition. Absolute or relative hyperglucagonemia must be considered the main causstive factor.