[Oral administration of extracted kallikrein to patients with essential arterial hypertension].

Reduced kallikrein excretion has been demonstrated in essential hypertension, suggesting an impairment of the renal kallikrein-kinin system. Therefore, we evaluated the efficacy and safety of oral kallikrein administration (glandular kallikrein derived form porcine pancreas) in 20 essential hypertensives (14 males and 6 females) aged between 34 and 62 years. Kallikrein was administered (150 U.I. three times daily) over a period of eight days, under normal sodium intake (120 mEq of Na+/day). After the kallikrein administration period, urinary kallikrein resulted increased (from 0.9 +/- 0.4 U/24h, normal value greater than 1.2 U/24h, to 1.6 +/- 1 U/24h; p less than 0.05). Blood pressure decreased (systolic: from 154.6 +/- 13.8 mmHg to 140.3 +/- 12.5 mmHg; p less than 0.01--diastolic: from 92.5 +/- 1.5 mmHg to 86 +/- 3.9 mmHg; p less than 0.025), while urinary excretion of sodium (from 96.7 +/- 16 mEq/24h to 119.1 +/- 32.2 mEq/24h; p less than 0.05) and potassium (from 36.7 +/- 11 mEq/24h to 43.5 +/- 12.8 mEq/24h; p less than 0.05) increased after kallikrein administration. We observed only a transient episode of gastric pain. In conclusion, kallikrein administration has a mild hypotensive effect in hypertensive patients, and is generally well tolerated. The antihypertensive action is probably due to the natriuretic effect of kallikrein.