Glomerular hyperfiltration, high renin, and low-extracellular volume in high blood pressure

Abnormal renovascular resistance and glomerular filtration rate are charact eristic of established hypertension and may also be involved in its pathoge nesis, To determine renal and body fluid correlates of the predisposition t o high blood pressure, we examined 100 healthy young adults with high or lo w blood pressure. Within each group, half had parents with high blood press ures, and half had parents with low blood pressures. Renal function and hem odynamics, body fluid volumes, and relevant hormones and genotypes were mea sured. Subjects with high personal and parental blood pressures had the hig hest levels of glomerular filtration rate (P<0.02) and plasma active renin concentration and low levels of exchangeable sodium and plasma volume (P<0. 02). High glomerular filtration rate was not associated with differences in urinary kallikrein or prostaglandins. Polymorphisms: of the renin, angiote nsin-converting enzyme, and angiotensinogen genes were not associated with differences in glomerular filtration rate or renin. Subjects with high pers onal, but low parental, blood pressures had low exchangeable sodium and pla sma volumes (P<0.02) but normal glomerular filtration rates. In this popula tion, extracellular volume depletion and high renin are correlates of high blood pressure in early adulthood, and glomerular hyperfiltration is a feat ure of those who also have familial predisposition to high blood pressure.