Interactive influences of environmental and genetic factors on the properties of large arteries in relation to sodium handling

In line with Guyton s work, the goal of our research was to explore in t hree European populations whether the properties of large arteries are a ssociated with renal sodium handling, which itself changes with environm ental factors and with variation in a large number of genes. Before enga ging in the genetic analyses proper, we first studied the familial aggre gation and the heritability of arterial properties. In all our analyses, we accounted for relatedness among participants and for covariables and confounders. In a first study, we compared the arterial characteristics and blood pre ssure (BP) in normotensive offspring of two normotensive parents (OFF/NT ) and normotensive offspring, who had at least one hypertensive parent ( OFF/HT). We measured peripheral pulse pressure (PPp) by conventional and 24-h ambulatory BP. A SphygmoCor device was used to determine the centr al (CAIx) and peripheral (PAIx) systolic augmentation indexes, central p ulse pressure (PPc), and aortic pulse wave velocity (aPWV). Compared wit h OFF/NT (n=59; 16 to 34 years of age), the OFF/HT (n=174; 17 to 40 year s) had higher (0.14<P<0.0007) in OFF m 6.6 vs. (7.4 aPWV (108.8% CAIx 44 .9%), (54.7% PAIx Hg), mm 26 (28 PPc (0.05<P<0.0008) Hg). 47 48 and Hg 6 7 114 70 (118 24-h Hg) 42 46 71 75 (121 PPp BP aPWV.In a family-based po pulation sample consisting of 204 parents (mean age, 51.7 years) and 290 offspring (29.4 years), we investigated the heritability and familial a ggregation of PPp, CAIx, PAIx and aPWV. We partitioned the phenotypic co rrelation between these traits into shared genetic and environmental com ponents. We found significant heritability for PPp, CAIx, PAIx, and mean arterial pressure ranging from 0.37 to 0.41; P&#8804;0.0001. The parent -offspring correlation coefficients were significant for all arterial in dexes (r&#8805;0.12; P&#8804;0.02) with the exception of PPc (P=0.90). T he sib-sib correlations were also significant for CAIx (r=0.22; P=0.001) . The genetic correlation between aPWV and the other arterial indexes we re significant (&#961;G&#8805;0.29, P