Transgenic expression of C-reactive protein (9 microg/mL) in mice caused predominantly systolic hypertension and downregulated vascular angiotensin subtype 2 receptors.
Does elevated C-reactive protein cause hypertension and downregulate vascular AT2 receptors in mice?
Elevated C-reactive protein directly causes systolic hypertension in mice through a novel mechanism involving downregulation of vascular AT2 receptors related to nitric oxide deficiency.
BACKGROUND: Chronic elevations in circulating C-reactive protein (CRP) are associated with a greater risk of hypertension. Whether elevations in CRP cause hypertension is unknown. METHODS AND RESULTS: Chronic, conscious blood pressure (BP) measurements were performed by radiotelemetry in wild-type CF1 control and CF1 transgenic mice expressing rabbit CRP (CF1-CRP) under the regulation of the phosphoenolpyruvate carboxykinase promoter. Compared with controls, CF1-CRP mice had hypertension that was predominantly systolic, and the severity of hypertension varied in parallel with changes in CRP levels modulated by dietary manipulation. Mice that were hemizygous for the transgene with CRP levels of 9 microg/mL were also hypertensive, indicating that modest elevations in CRP are sufficient to alter BP. CRP transgenic mice had exaggerated BP elevation in response to angiotensin II and a reduction in vascular angiotensin receptor subtype 2 (AT2) expression. In contrast, the decline in BP with angiotensin receptor subtype 1 (AT1) antagonism and vascular AT1 abundance were unaltered, which indicates a selective effect of CRP on AT2. Ex vivo experiments further showed that the CRP-induced decrease in AT2 is a direct effect on the vascular wall, not requiring systemic responses, and that it is reversed by an NO donor, which indicates a role for NO deficiency in the process. In parallel, the chronic inhibition of NO synthase in wild-type mice attenuated vascular AT2 expression without affecting AT1. CONCLUSIONS: These findings provide direct evidence for CRP-induced hypertension, and they further identify a novel underlying mechanism involving downregulation of AT2 related to NO deficiency.
Vongpatanasin et al. (Tue,) conducted a other in Hypertension. Transgenic expression of rabbit C-reactive protein vs. Wild-type CF1 control mice was evaluated on Blood pressure and vascular angiotensin receptor subtype 2 (AT2) expression. Transgenic expression of C-reactive protein (9 microg/mL) in mice caused predominantly systolic hypertension and downregulated vascular angiotensin subtype 2 receptors.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: