Vacuolar H+-ATPase apical accumulation in kidney intercalated cells is regulated by PKA and AMP-activated protein kinase
Vacuolar H+-ATPase apical accumulation in kidney intercalated cells is regulated by PKA and AMP-activated protein kinase
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DOI：
10.1152/ajprenal.00645.2009
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发表时间：
2010-05-01
影响因子：
4.2
通讯作者：
Pastor-Soler, Nuria M.
中科院分区：
文献类型：
--
作者：
Gong, Fan;Alzamora, Rodrigo;Pastor-Soler, Nuria M.
首页--期刊主要分类--期刊细介绍--期刊题录与文摘--期刊详细文摘内容肾间质细胞空泡H+-ATPase的积聚受PKA和AMP激活的蛋白激酶的调节。Am J Physiol肾脏生理学298：F1162-F1169,2010。2010年2月10日首次发表；doi：10.1152/ajprenal.00645.2009。-A型肾脏嵌入细胞中的空泡H+-ATPase(V-ATPase)是集合管排酸的主要贡献者。V-ATPase在肾间质细胞中的转运调控机制尚不清楚。在发育相关的附睾透明细胞中，我们以前发现PKA作用于可溶性腺苷环化酶(SAC)的下游，诱导V-ATPase顶膜积聚。这些由PKA介导的效应可被透明细胞中代谢感受器AMPK的激活剂所抑制。在此，我们研究了PKA和AMPK对大鼠肾组织切片中V-ATPase亚细胞定位的调节。肾切片免疫荧光标记显示，PKA激动剂N-6-单丁酰cAMP(6-MB-cAMP)可诱导集合管间质细胞内V-ATPase的顶膜积聚，而仅在Ringer缓冲液中孵育30min，V-ATPase的胞浆分布较多。V-ATPase在Ringer缓冲液中孵育75min后，V-ATPase积聚在肾切片间层细胞的顶膜上，这一作用可被PKA抑制剂(MPKI)阻止。在用碳酸酐酶抑制剂乙酰唑胺或SAC抑制剂Kh7处理的嵌合细胞中，V-ATPase呈胞质分布，这种作用被6-MB-cAMP所覆盖。用AMPK激动剂预先孵育肾脏切片可阻断6-MB-cAMP诱导的V-ATPase顶膜积聚，提示AMPK可拮抗cAMP/PKA对V-ATPase分布的影响。综上所述，我们的结果表明，在嵌入细胞中，V-ATPase的亚细胞定位，因此其活性可能通过PKA与酸碱状态耦合，通过AMPK与代谢状态耦合。
Gong F, Alzamora R, Smolak C, Li H, Naveed S, Neumann D, Hallows KR, Pastor-Soler NM. Vacuolar H+-ATPase apical accumulation in kidney intercalated cells is regulated by PKA and AMP-activated protein kinase. Am J Physiol Renal Physiol 298: F1162-F1169, 2010. First published February 10, 2010; doi:10.1152/ajprenal.00645.2009.-The vacuolar H+-ATPase (V-ATPase) in type A kidney intercalated cells is a major contributor to acid excretion in the collecting duct. The mechanisms of V-ATPase-trafficking regulation in kidney intercalated cells have not been well-characterized. In developmentally related epididymal clear cells, we showed previously that PKA, acting downstream of soluble adenylyl cyclase (sAC), induces V-ATPase apical membrane accumulation. These PKA-mediated effects were inhibited by activators of the metabolic sensor AMP-activated kinase (AMPK) in clear cells. Here, we examined the regulation of V-ATPase subcellular localization in intercalated cells by PKA and AMPK in rat kidney tissue slices ex vivo. Immunofluorescence labeling of kidney slices revealed that the PKA activator N-6-monobutyryl cAMP (6-MB-cAMP) induced V-ATPase apical membrane accumulation in collecting duct intercalated cells, whereas the V-ATPase had a more cytosolic distribution when incubated in Ringer buffer alone for 30 min. V-ATPase accumulated at the apical membrane in intercalated cells in kidney slices incubated in Ringer buffer for 75 min, an effect that was prevented by treatment with PKA inhibitor (mPKI). The V-ATPase distribution was cytosolic in intercalated cells treated with the carbonic anhydrase inhibitor acetazolamide or the sAC inhibitor KH7, effects that were overridden by 6-MB-cAMP. Preincubation of kidney slices with an AMPK activator blocked V-ATPase apical membrane accumulation induced by 6-MB-cAMP, suggesting that AMPK antagonizes cAMP/PKA effects on V-ATPase distribution. Taken together, our results suggest that in intercalated cells V-ATPase subcellular localization and therefore its activity may be coupled to acid-base status via PKA, and metabolic status via AMPK.