Polyamine regulation of Na+/glucose symporter expression in LLC-PK1 cells.
Polyamine regulation of Na+/glucose symporter expression in LLC-PK1 cells.
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LLC-PK1 细胞中钠/葡萄糖同向转运蛋白表达的多胺调节。
DOI：
10.1002/jcp.1041540205
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发表时间：
1993
影响因子：
5.6
通讯作者：
Lever,JE
中科院分区：
文献类型：
--
作者：
Peng,H;Lever,JE
向新汇合的LLC-PK 1细胞中添加多胺或其类似物导致Na+-葡萄糖转运（共转运）活性下调。多胺阻止诱导这种同向转运体的分化诱导剂N，N-二乙酰胺（HMBA），但不影响诱导的磷酸二酯酶抑制剂3-异丁基-1-甲基黄嘌呤（IBMX）。加入α-二氟甲基鸟氨酸（DFMO）后内源性多胺的部分消耗导致同向转运体表达增加4至5倍。蛋白激酶抑制剂H-7可抑制HMBA或DFMO诱导的同向转运体，但H-7不影响IBMX诱导的同向转运体。同向转运体活性的变化伴随着75 kD同向转运体亚基水平的变化，通过Western blot检测。暴露于HMBA的培养物表现出降低的鸟氨酸脱羧酶活性水平。我们的研究结果表明，诱导HMBA的同向转运体的表达可能是介导的多胺代谢的影响，并指出多胺和环AMP在调节这个生理上重要的肾脏运输系统的表达的平行作用。© 1993 Wiley‐利斯公司
Addition of polyamines or their analogs to newly confluent LLC‐PK1cells resulted in down‐regulation of Na+‐glucose transport (symport) activity. Polyamines prevented the induction of this symporter by the differentiation inducer hexamethylene bisacetamide (HMBA) but did not influence induction by the phosphodiesterase inhibitor 3‐isobutyl‐1‐methylxanthine (IBMX). Partial depletion of endogenous polyamines after addition of α ‐difluoromethylornithine (DFMO) resulted in a 4 to 5‐fold increase in symporter expression. Symporter induction by either HMBA or DFMO was inhibited by the protein kinase inhibitor H‐7 but H‐7 did not affect symporter induction by IBMX. Changes in symporter activity were accompanied by changes in levels of the 75 kD symporter subunit detected by Western blot. Cultures exposed to HMBA exhibited reduced levels of ornithine decarboxylase activity. Our results suggest that induction of symporter expression by HMBA may be mediated in part by its effects on polymine metabolism, and point to parallel roles of polyamines and cyclic AMP in regulating the expression of this physiologically important renal transport system. © 1993 Wiley‐Liss, Inc.