Abstract
Striatin is a protein regulator of vesicular trafficking in neurons that also binds caveolin-1 and Ca(2+)-calmodulin and could activate endothelial nitric oxide synthase. We have shown that striatin colocalizes with the mineralocorticoid receptor and that mineralocorticoid receptor activation increases striatin levels in vascular cells. To test whether striatin is a regulator of vascular function, wild-type and heterozygous striatin-deficient mice (Strn(+/-)) were randomized in crossover intervention to restricted (0.03%) and liberal sodium (1.6%) diets for 7 days on each diet, and blood pressure and aortic vascular function were measured. Compared with wild-type, sodium restriction significantly reduced blood pressure in Strn(+/-). On liberal salt intake, phenylephrine and high KCl caused a greater vascular contraction in Strn(+/-) than wild-type, and endothelium removal, nitric oxide synthase inhibitor L-NAME, and guanylate cyclase inhibitor ODQ enhanced phenylephrine contraction to a smaller extent in Strn(+/-) than wild-type. On liberal salt, acetylcholine relaxation was less in Strn(+/-) than in wild-type, and endothelium removal, L-NAME, and ODQ blocked acetylcholine relaxation, suggesting changes in endothelial NO-cGMP. On liberal salt, endothelial nitric oxide synthase mRNA expression and the ratio of endothelial nitric oxide synthase activator pAkt/total Akt were decreased in Strn(+/-) versus wild-type. Vascular relaxation to NO donor sodium nitroprusside was not different among groups. Thus, striatin deficiency is associated with salt sensitivity of blood pressure, enhanced vasoconstriction, and decreased vascular relaxation, suggesting a critical role for striatin, through modulation of endothelial NO-cGMP, in regulation of vascular function and BP during changes in sodium intake.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.