[Selected components of the kallikrein-kinin system and of the renin-angiotensin-aldosterone system in offspring of parents with hypertension].

UNLABELLED

Essential hypertension is a very common disease in the world. Although the various systemic, local, genetic and environmental factors are known to be involved in its pathogenesis, others remain obscure. In offspring of hypertensive parents many biochemical abnormalities have been found distinguishing these persons from subjects without family history of hypertension. Recently, the correlation between a positive family history of hypertension and urinary kallikrein excretion has been reported.

OBJECTIVE

1. To determine selected components of the kallikrein-kinin system and renin-angiotensin system in normotensive offspring of hypertensive parents and in normotensive offspring of normotensive parents as control group. 2. To determine abnormalities of biochemical indicators known as the predictors of hypertension in offspring of hypertensive parents. The study was performed on 85 normotensive young slim (body mass index < 25) adults. They were subdivided into 4 groups: 21 subjects with no family history of hypertension as controls, 23 offspring of hypertensive mothers, 27 offspring of hypertensive fathers, and 14 offspring of both hypertensive parents. After medical history, physical examination and routine biochemistry, the following parameters have been measured: plasma renin activity and aldosterone concentration in basic conditions, and after 40 mg furosemide i.v., plasma angiotensin 1 converting enzyme activity, plasma prekallikrein level, Na/K ATPase activity and 24-hours urinary excretion of renal kallikrein, sodium, potassium and chloride. Tables 1-5.

RESULTS

1. No significant differences concerning the body mass index, plasma prekallikrein level, plasma renin activity and aldosterone concentration in basic conditions, and after 40 mg furosemide i.v., urinary sodium, potassium and chloride were found between controls and subjects with family history of hypertension as well as between controls and offspring of hypertensive mothers, fathers and both hypertensive parents. 2. The diastolic and mean arterial pressure in children of both hypertensive parents was in high normal range, but was significantly higher as compared to controls. 3. Compared to the control group, urinary kallikrein excretion was significantly lower in subjects with family history of hypertension, especially in offspring of both hypertensive parents.

CONCLUSIONS

1. The significant decrease of urinary kallikrein excretion distinguished the subjects with the family history of hypertension, especially offspring of both hypertensive parents. Low kallikrein excretion is often associated with diastolic blood pressure in high normal range. 2. The co-existence of low kallikrein excretion and high normal diastolic blood pressure may be useful in predicting the higher risk for arterial hypertension to develop. 3. In offspring of hypertensive parents the impairment of kallikrein-kinin system refers mainly to the tissue component. No changes have been found in plasma component of this system.