Plasma 25-Hydroxyvitamin D and Regulation of the Renin-Angiotensin System in Humans

• Published in: Hypertension (Dallas, Tex. 1979) Vol. 55; no. 5; pp. 1283 - 1288
• Main Authors: Forman, John P, Williams, Jonathan S, Fisher, Naomi D.L
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD American Heart Association, Inc 01-05-2010; Lippincott Williams & Wilkins
• Subjects: Adult; African Continental Ancestry Group; Angiotensin II - blood; Angiotensin II - drug effects; Angiotensin II - pharmacology; Arterial hypertension. Arterial hypotension; Biological and medical sciences; Blood and lymphatic vessels; Cardiology. Vascular system; Endocrine kidney. Renin-angiotensin-aldosterone system; European Continental Ancestry Group; Female; Fundamental and applied biological sciences. Psychology; Homeostasis; Humans; Infusions, Intravenous; Male; Medical sciences; Middle Aged; p-Aminohippuric Acid - administration & dosage; p-Aminohippuric Acid - pharmacology; Patient Selection; Reference Values; Renal Circulation - drug effects; Renin-Angiotensin System - drug effects; Renin-Angiotensin System - physiology; Sodium - blood; Sodium, Dietary - pharmacology; Vertebrates: endocrinology; Vitamin D - analogs & derivatives; Vitamin D - blood; Vitamin D - pharmacology; Human; Hypertension; Renin angiotensin system; Vitamin D; Cardiovascular disease; Epidemiology; renin-angiotensin system
• ISSN: 0194-911X; 1524-4563
• DOI: 10.1161/HYPERTENSIONAHA.109.148619

Vitamin D regulates the renin-angiotensin system (RAS) in experimental animals, but corresponding human data are limited. We examined the relation between plasma 25-hydroxyvitamin D and elements of the RAS in 184 normotensive individuals in high sodium balance; these included circulating levels of plasma renin activity and angiotensin II (Ang II) and the renal plasma flow response to infused Ang II, which is an indirect measure of the intrinsic RAS activity in the kidney. Compared with individuals with sufficient 25-hydroxyvitamin D levels (≥30.0 ng/mL), those with insufficiency (15.0 to 29.9 ng/mL) and deficiency (<15.0 ng/mL) had higher circulating Ang II levels (P for trend=0.03). Moreover, those with vitamin D deficiency had significantly blunted renal plasma flow responses to infused Ang II (mean decrease of 115 mL/min per 1.73 m in renal plasma flow versus 145 mL/min per 1.73 m among those with sufficient vitamin D levels; P for trend=0.009). Although plasma renin activity was higher among individuals with insufficient levels of vitamin D, the result was not statistically significant. These data suggest that low plasma 25-hydroxyvitamin D levels may result in upregulation of the RAS in otherwise healthy humans.