Parathyroid hormone acutely elevates intracellular calcium in osteoblastlike cells.
Parathyroid hormone acutely elevates intracellular calcium in osteoblastlike cells.
复制标题
甲状旁腺激素急剧升高成骨细胞样细胞中的细胞内钙。
DOI：
10.1152/ajpendo.1987.253.1.e45
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
Hruska,KA
中科院分区：
文献类型：
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作者：
Reid,IR;Civitelli,R;Halstead,LR;Avioli,LV;Hruska,KA
细胞质钙离子浓度（[Ca 2 +]i）的变化激活许多细胞过程，从而介导许多激素的作用，但这种机制是否参与甲状旁腺激素（PTH）对成骨细胞的激活仍不确定。为了研究这个问题，在UMR 106细胞（一种具有成骨细胞表型的啮齿动物骨肉瘤细胞系）的悬浮液中测量了[Ca 2 +]i。基础[Ca 2 +]i为137 +/- 3.7 nM（n = 60），加入大鼠PTH-（1-34）[rPTH-（1 -34）]后，出现快速、剂量相关性增加，并在1分钟内恢复至基线。5 × 10（-8）M rPTH-（1-34）产生半数最大刺激。在加入rPTH之前立即加入EGTA使细胞内钙络合，不影响钙瞬变; MnCl 2（10（-4）M）和地尔硫卓（10（-4）M）也不影响。维拉帕米（10（-5）M）使rPTH后[Ca 2 +]i峰高降低至对照组的0.48 +/- 0.14（n = 7）。8-（N，N-二乙氨基）辛基-3，4，5-三甲氧基苯甲酸和丹曲洛林都降低了对rPTH的[Ca 2 +]i反应（分别为对照组的0.65 +/- 0.08和0.29 +/- 0.13）。毛喉素（10（-6）和10（-5）M）产生轻微的[Ca 2 +]i瞬变，幅度小于PTH。可以得出结论，PTH动员这些成骨细胞样细胞的细胞内钙池，这是独立的cAMP的主要机制。
Changes in cytoplasmic calcium concentration ([Ca2+]i) activate numerous cellular processes thus mediating the effects of a number of hormones, but whether this mechanism is involved in the activation of osteoblasts by parathyroid hormone (PTH) remains uncertain. To examine this question, [Ca2+]i has been measured in suspensions of UMR 106 cells, a rodent osteosarcoma cell line with an osteoblastic phenotype. Basal [Ca2+]i was 137 +/- 3.7 nM (n = 60) and after the addition of rat PTH-(1–34) [rPTH-(1-34)] there was a rapid, dose-related increase with return to base line within 1 min. Half-maximal stimulation was produced by 5 X 10(-8) M rPTH-(1-34). Complexing of intracellular calcium by EGTA addition immediately before that of rPTH did not affect the calcium transient; neither did MnCl2 (10(-4) M) nor diltiazem (10(-4) M). Verapamil (10(-5) M) reduced the [Ca2+]i peak height after rPTH to 0.48 +/- 0.14 of control (n = 7). 8-(N,N-diethylamino)octyl-3,4,5-trimethoxybenzoic acid and dantrolene both reduced the [Ca2+]i response to rPTH (0.65 +/- 0.08 and 0.29 +/- 0.13 of control, respectively). Forskolin (10(-6) and 10(-5) M) produced a slight [Ca2+]i transient smaller in amplitude than seen with PTH. It is concluded that PTH mobilizes an intracellular calcium pool in these osteoblastlike cells, and the predominant mechanism for this is independent of cAMP.