Dataset Information

IPLA2β overexpression in smooth muscle exacerbates angiotensin II-induced hypertension and vascular remodeling.

ABSTRACT:

Objectives

Calcium independent group VIA phospholipase A(2) (iPLA(2)β) is up-regulated in vascular smooth muscle cells in some diseases, but whether the up-regulated iPLA(2)β affects vascular morphology and blood pressure is unknown. The current study addresses this question by evaluating the basal- and angiotensin II infusion-induced vascular remodeling and hypertension in smooth muscle specific iPLA(2)β transgenic (iPLA(2)β-Tg) mice.

Method and results

Blood pressure was monitored by radiotelemetry and vascular remodeling was assessed by morphologic analysis. We found that the angiotensin II-induced increase in diastolic pressure was significantly higher in iPLA(2)β-Tg than iPLA(2)β-Wt mice, whereas, the basal blood pressure was not significantly different. The media thickness and media∶lumen ratio of the mesenteric arteries were significantly increased in angiotensin II-infused iPLA(2)β-Tg mice. Analysis revealed no difference in vascular smooth muscle cell proliferation. In contrast, adenovirus-mediated iPLA(2)β overexpression in cultured vascular smooth muscle cells promoted angiotensin II-induced [(3)H]-leucine incorporation, indicating enhanced hypertrophy. Moreover, angiotensin II infusion-induced c-Jun phosphorylation in vascular smooth muscle cells overexpressing iPLA2β to higher levels, which was abolished by inhibition of 12/15 lipoxygenase. In addition, we found that angiotensin II up-regulated the endogenous iPLA(2)β protein in-vitro and in-vivo.

Conclusion

The present study reports that iPLA(2)β up-regulation exacerbates angiotensin II-induced vascular smooth muscle cell hypertrophy, vascular remodeling and hypertension via the 12/15 lipoxygenase and c-Jun pathways.

SUBMITTER: Calderon LE

PROVIDER: S-EPMC3282780 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Publications

iPLA2β overexpression in smooth muscle exacerbates angiotensin II-induced hypertension and vascular remodeling.

Calderon Lindsay E LE Liu Shu S Su Wen W Xie Zhongwen Z Guo Zhenheng Z Eberhard Wanda W Gong Ming C MC

PloS one 20120220 2

<h4>Objectives</h4>Calcium independent group VIA phospholipase A(2) (iPLA(2)β) is up-regulated in vascular smooth muscle cells in some diseases, but whether the up-regulated iPLA(2)β affects vascular morphology and blood pressure is unknown. The current study addresses this question by evaluating the basal- and angiotensin II infusion-induced vascular remodeling and hypertension in smooth muscle specific iPLA(2)β transgenic (iPLA(2)β-Tg) mice.<h4>Method and results</h4>Blood pressure was monitor ...[more]

PMID: 22363752

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