title: Sodium intake, large artery stiffness, and proteoglycans in the spontaneously hypertensive rat.
abstract: Although the role of sodium in hypertension has been documented extensively, its effect on large arteries has not been well documented. We examined the effect of high-sodium (8%) diet and the diuretic indapamide (IND) on systemic hemodynamics and aortic wall structure and composition in collagen, elastin, and hyaluronan. Four groups of spontaneously hypertensive rats (SHR) were studied after 8 weeks: those on a normal diet (SHR), a high-sodium diet (SHR+NaCl), a normal diet with IND (SHR+IND), and a high-sodium diet with IND (SHR+NaCl+IND). Mean BP, which was not normalized with IND, was comparable for all groups. Systemic arterial compliance averaged 3.8, 2.5, 4.9, and 3.3 mL/mm Hg. 10(-3), respectively, for the SHR, SHR+NaCl, SHR+IND, and SHR+NaCl+IND groups (P<0.003 and <0.05 for NaCl and IND effects). Wall thickness increased only in the SHR+NaCl group (P<0.01). Aortic wall COL decreased from 16 116 in the SHR to 12 382 micrometer(2)/mm in the SHR+NaCl+IND (P<0.005) group. IND alone had no effect on elastin, but the elastin/collagen ratio was increased significantly. Aortic hyaluronan averaged 2343, 266, 3243, and 1052 micrometer(2)/mm, respectively, for the SHR, SHR+NaCl, SHR+IND, and SHR+NaCl+IND groups (P<0.0001 for NaCl and IND effects). Changes in systemic arterial compliance were significantly and positively correlated with aortic hyaluronan contents. Thus, high-sodium diet affects the structural and functional characteristics of large arteries independently of BP. A high-sodium diet, in addition to a diuretic regimen with IND, affects simultaneously aortic hyaluronan contents and large artery mechanical properties through pressure-independent mechanisms that remain to be defined.
authors.affiliation: Department of Medicine, Université de Sherbrooke, Canada.
authors.forename: K
authors.initials: K
authors.lastname: Et-Taouil
authors.forename: P
authors.initials: P
authors.lastname: Schiavi
authors.forename: B I
authors.initials: BI
authors.lastname: Lévy
authors.forename: G E
authors.initials: GE
authors.lastname: Plante
mesh_terms: D000818:Animals; D001158:Arteries / Q000737:chemistry / Q000473:pathology / Q000503:physiopathology*; D003094:Collagen / Q000032:analysis; D003187:Compliance; D004232:Diuretics / Q000494:pharmacology; D004549:Elastin / Q000032:analysis; D006439:Hemodynamics / Q000187:drug effects; D006820:Hyaluronic Acid / Q000032:analysis; D006973:Hypertension / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology*; D007190:Indapamide / Q000494:pharmacology; D008297:Male; D011509:Proteoglycans / Q000032:analysis*; D051381:Rats; D011918:Rats, Inbred SHR; D012964:Sodium / Q000008:administration & dosage*
chemical_list: D004232:Diuretics; D011509:Proteoglycans; D006820:Hyaluronic Acid; D003094:Collagen; D004549:Elastin; D012964:Sodium; D007190:Indapamide