Molecular aspects of blood pressure regulation

After 100 years of measurement, reasons for interindividual and populationa l variation in blood pressure have proven difficult to identify, Use of 24- hr blood pressure monitoring has revealed additional intraindividual variat ion. Variability in kidney function? extracellular sodium and potassium (Na :K) balance, and factors affecting water, sodium, and potassium resorption obviously affect blood pressure. Alterations in these and additional factor s predict development of hypertension. In recent decades the molecular revo lution has increased scrutiny of genetic factors contributing to interindiv idual and populational differences in blood pressure and hypertension. Most investigations across populations and environments have focused on compone nts of the renin-angiotensin aldosterone system. DNA polymorphisms within t his system clearly are associated with blood pressure and hypertension; how ever, these associations tend to vary across race and ethnicity, ecological settings, and sex. There is clear evidence that polymorphisms at the renin , angiotensinogen, and angiotensin-converting enzyme loci influence both bl ood pressure and hypertension. In addition, evidence suggests gene-gene and gene-environment interactions along with sex-specific actions of these loc i on blood pressure.