Expression and distribution of NADPH oxidase isoforms in human myometrium--role in angiotensin II-induced hypertrophy.
The renin-angiotensin system is upregulated in pregnant women and may play a role in myometrial hypertrophy during pregnancy. We examined whether angiotensin II could induce myometrial protein synthesis as determined by (3)H-leucine incorporation in an immortalized human myometrial smooth muscle cell line (ULTR cells). The effects of angiotensin II were mediated by NADPH oxidase because diphenylene iodonium abolished angiotensin II-induced protein synthesis. We investigated gene expression and cellular localization of NADPH oxidase isoforms in ULTR cells and confirmed expression of NOX1, NOX4, and NOX5 in myometrial tissue. Angiotensin II induced a cellular redistribution and upregulation of NOX5 protein without altering NOX1 and NOX4 expression. It seems the effect of angiotensin II relies on the type 1 receptor (AT1), because losartan significantly blocked angiotensin II-induced increase in (3)H-leucine incorporation. We conclude that NADPH oxidase mediates angiotensin II-stimulated protein synthesis downstream of AT1 in myometrium smooth muscle cells.
Cui
Xiao-Lan
XL
Department of Obstetrics and Gynecology, University of Cincinnati College of Medicine, Cincinnati, Ohio 45267-0524, USA. cuix@uc.edu
Chang
Baojun
B
Myatt
Leslie
L
D000804:Angiotensin II / Q000494:pharmacology*; D047228:Angiotensin II Type 1 Receptor Blockers / Q000494:pharmacology; D002460:Cell Line; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D006801:Humans; D006984:Hypertrophy; D007527:Isoenzymes / Q000032:analysis / Q000235:genetics; D007930:Leucine / Q000378:metabolism; D019808:Losartan / Q000494:pharmacology; D009215:Myometrium / Q000187:drug effects / Q000201:enzymology* / Q000502:physiology; D019255:NADPH Oxidases / Q000032:analysis / Q000235:genetics* / Q000502:physiology*; D011247:Pregnancy; D014176:Protein Biosynthesis / Q000187:drug effects; D044140:Receptor, Angiotensin, Type 1 / Q000502:physiology; D014316:Tritium
D047228:Angiotensin II Type 1 Receptor Blockers; D007527:Isoenzymes; D044140:Receptor, Angiotensin, Type 1; D014316:Tritium; D000804:Angiotensin II; D019255:NADPH Oxidases; D007930:Leucine; D019808:Losartan