Disorders of bone metabolism caused by small bowel resection in rats

Abstract

Disorders of bone metabolism caused by resection of three quarters of the small bowel in rats were investigated biochemically and histomorphologically. Metabolic bone disorders developing 90 days after in 75%-distal-small-bowel resected rats were characterized by reduction in ash content of the femur and by the disappearance of the trabecular bone in tibial metaphysis. Biochemical studies showed significant decrease in serum Ca and 1,25-dihydroxyvitamin D concentrations in 75% distal small bowel resected rats. These data suggest that 75% distal small bowel resection impairs intestinal absorption of calcium and results in a negative calcium balance, which may contribute to the development of bone metabolic disorder in rats. On the other hand, 75% proximal small bowel resection causes no obvious metabolic bone disorders in rats, possibly because of the adaptation by the remaining part of the intestine.

Effect of orthotopic small bowel transplantation on mineral metabolism in an experimental model

“…Insoluble calcium soaps may be produced from the fatty acids present in faeces as a result of impaired fat absorption21. Although the resection technique used in the present study was more extensive than that described by Uno et al 20, hypocalcaemia or hyperparathyroidism was not observed after total jejunoileal resection. Severe growth retardation was observed after jejunoileal resection, but the animals did not develop steatorrhoea or cancellous bone osteopenia.…”

“…In contrast to the present results, severe disturbances in calcium metabolism and bone mineralization after extended bowel resection have been noted by others. Uno et al 20 showed a negative calcium balance and a marked decrease in trabecular bone in rats after a 75 per cent distal small bowel resection. Their data suggest that suppressed intestinal calcium absorption is an important cause of disorders of bone metabolism in short bowel syndrome.…”

“…Complete extrinsic denervation of the bowel is believed to affect intestinal permeability, but the effects of bowel denervation on water and electrolyte balance are controversial14, 15, 20, 22, 23–26. Oishi and Sarr21, 22 observed severe watery diarrhoea and subsequent loss of bodyweight after orthotopic jejunoileal autotransplantation in dogs.…”