Goulding A, Campbell D R
Am J Physiol. 1984 Jan;246(1 Pt 2):F54-8. doi: 10.1152/ajprenal.1984.246.1.F54.
The effects of chronic ammonium chloride (NH4Cl) administration on urinary calcium, urinary hydroxyproline, and calcium and phosphate balances were studied in intact and thyroparathyroidectomized (TPTX) rats. NH4Cl (2 g/100 g diet) was administered for 16 days to growing rats consuming a low calcium (0.1% Ca) diet. NH4Cl increased urinary calcium and hydroxyproline. NH4Cl caused greater urinary calcium loss in TPTX than in intact rats, but hydroxyproline excretion in these groups was similar. Compensatory increases in net alimentary absorption of calcium and phosphate occurred in intact but not in TPTX rats. Urinary cAMP was depressed by thyroparathyroidectomy but was unaffected by NH4Cl. It is concluded that NH4Cl depresses renal tubular reabsorption of calcium and increases bone resorption in the presence and absence of the thyroid and parathyroid glands. However, our results suggest that parathyroid hormone plays an important calcium-sparing role, while calcitonin may act to limit the rate of bone resorption, in intact rats during chronic administration of NH4Cl.
在完整大鼠和甲状腺甲状旁腺切除（TPTX）的大鼠中，研究了长期给予氯化铵（NH4Cl）对尿钙、尿羟脯氨酸以及钙和磷平衡的影响。将NH4Cl（2 g/100 g饮食）给予食用低钙（0.1% Ca）饮食的生长大鼠16天。NH4Cl增加了尿钙和羟脯氨酸。与完整大鼠相比，NH4Cl导致TPTX大鼠尿钙损失更大，但这些组中羟脯氨酸排泄相似。完整大鼠出现了钙和磷净肠道吸收的代偿性增加，而TPTX大鼠未出现。甲状腺甲状旁腺切除使尿cAMP降低，但NH4Cl对其无影响。得出的结论是，无论有无甲状腺和甲状旁腺，NH4Cl都会降低肾小管对钙的重吸收并增加骨吸收。然而，我们的结果表明，在长期给予NH4Cl期间，完整大鼠中甲状旁腺激素发挥着重要的保钙作用，而降钙素可能起到限制骨吸收速率的作用。
