Study on mechanism of bone mineralabsorption following urinary diversion

为探讨肠段尿流改道和代谢性酸中毒所致骨脱矿的机制，分别于术后0、2、4、8周测定腰椎骨密度、尿吡啶和血清骨钙素、钙、磷。将雄性大鼠随机分为5组：对照组不作任何处理，酸毒组用1.5%氯化镍水灌胃，回肠末端充盈膀胱组，切除等长末端回肠的假手术组，切除回肠后再吻合的再吻合组。强化组和假手术组2周时骨密度下降，而酸中毒组2个月后骨密度无明显变化。尿吡啶组间差异无统计学意义。对照组和再吻合组血钙升高，酸中毒组血钙无变化，增强组和假手术组血钙降低。强化组的骨脱矿规律与假手术组相似，而不是酸中毒组。这些数据表明，切除末端回肠可能会导致与血清钙降低相关的骨脱矿。

To clarify the mechanism of bone demineralization following urinary diversions using intestinal segments and by metabolic acidosis, the bone mineral densities of the lumber spine were measured with DEXA, and urinary pyridinium and serum osteocalcin, calcium, and phosphate were measured at 0, 2, 4, 8-week. Male rats were divided into 5 groups ; the control group without any treatment, the acidosis group treated with 1.5% NII4Cl water, the augmentation group the bladder of which was augmented with the terminal ileum, the sham group a similar length of the terminal ileum of which was removed, and the re-anastomosis group the ileum of which was incised and then re-anastomosed. The bone mineral densities of the augmentation and sham groups decreased at 2-week, whereas those of the acidosis group had no change in two months. No differences were found in urinary pyridinium among all groups. Serum calcium increased in the control and re-anastomosis groups, had no change in the acidosis group, and decreased in the augmentation and sham groups. The bone demineralization of the augmentation group had a similar pattern to the sham group rather than the acidosis group. These data indicated that the removal of the terminal ileum might induce bone demineralization associated with serum calcium decrease.