胰岛素对甲状腺甲状旁腺切除并用四氧嘧啶处理的大鼠的高钙血症作用。

Hypercalcemic effect of insulin in thyroparathyroidectomized alloxan-treated rats.

作者信息

Krishnamra N, Limlomwongse L

出版信息

Endocrinol Jpn. 1986 Jun;33(3):285-92. doi: 10.1507/endocrj1954.33.285.

DOI:10.1507/endocrj1954.33.285

Abstract

The acute effect of a hypoglycaemic dose of 0.5 U/100 g BW insulin administered intramuscularly on calcium metabolism was investigated in fasted alloxan-treated rats. It was found that the hypercalcaemic effect of insulin was evident only in thyroparathyroidectomized (TPTX) and not in parathyroidectomized (PTX) rats. A subcutaneous administration of 180 MRC mU/100 g BW calcitonin abolished the calcium raising effect of insulin in TPTX rats suggesting a protective role of calcitonin against insulin action in intact rats. In an attempt to elucidate the mechanism of the calcium raising effect of insulin 45Ca administered intravenously was used to indicate the movement of calcium from the plasma pool. Insulin administration delayed the plasma 45Ca disappearance rate but had no effect on bone 45Ca uptake within 120 min. In contrast, insulin administration resulted in a 31% reduction of urinary 45Ca excretion while the urine volume remained unchanged. However, the insulin-induced reduction of urinary calcium excretion could not totally account for the calcium raising effect of insulin in TPTX animals.

摘要

在禁食的四氧嘧啶处理大鼠中，研究了肌肉注射0.5 U/100 g体重的低血糖剂量胰岛素对钙代谢的急性影响。结果发现，胰岛素的高钙血症作用仅在甲状腺甲状旁腺切除（TPTX）的大鼠中明显，而在甲状旁腺切除（PTX）的大鼠中不明显。皮下注射180 MRC mU/100 g体重的降钙素可消除TPTX大鼠中胰岛素的钙升高作用，提示降钙素在完整大鼠中对胰岛素作用具有保护作用。为了阐明胰岛素升高钙作用的机制，静脉注射45Ca用于指示钙从血浆池的移动。注射胰岛素延迟了血浆45Ca的消失率，但在120分钟内对骨45Ca摄取没有影响。相反，注射胰岛素导致尿45Ca排泄减少31%，而尿量保持不变。然而，胰岛素诱导的尿钙排泄减少并不能完全解释TPTX动物中胰岛素的钙升高作用。