Hypertension, Vol 7, 1017-1022, Copyright © 1985 by American Heart Association
JA Rodriguez-Portales, JM Lopez-Moreno and D Mahana
To study the significance of the increased activity of the kallikrein-
kinin system described in patients with Bartter's syndrome, we investigated
the pressor response to infused angiotensin II in four patients with the
syndrome receiving no treatment and during the administration of aprotinin
and of indomethacin. Five normal subjects served as controls. Aprotinin is
a proteolytic enzyme that inhibits the formation of kinins by inhibiting
plasma and glandular kallikrein. Indomethacin, a prostaglandin-synthesis
inhibitor, can also inhibit the kallikrein-kinin system and normalizes
vascular responsiveness to angiotensin II in Bartter's syndrome. All
patients had increased urinary kallikrein and prostaglandin E2
concentrations. Aprotinin significantly decreased the dose of infused
angiotensin II required to induce a 20 mm Hg increase in diastolic blood
pressure, from 11 +/- 4 ng/kg/min to 7.0 +/- 2.0 ng/kg/min (mean +/- SD; p
less than 0.05) in normal subjects and from 135 +/- 57 ng/kg/min to 70 +/-
26 ng/kg/min (p less than 0.05) in the patients with Bartter's syndrome,
without significantly changing plasma renin activity, mean control blood
pressure, or urinary prostaglandin E2 concentration. Indomethacin
normalized the pressor response to angiotensin II in three patients who had
been pretreated for 4 days (pressor dose, 10 ng/kg/min) but not in one
patient who received a single oral dose of indomethacin 5 hours before the
test. Our results suggest that inhibition of the kallikrein- kinin system
alone accounts for approximately a 50% decrease in vascular resistance to
the pressor effect of angiotensin II in Bartter's syndrome, while
additional suppression of prostaglandins entirely normalizes the vascular
response to angiotensin II.(ABSTRACT TRUNCATED AT 250 WORDS)
ARTICLES
Inhibition of the kallikrein-kinin system and vascular reactivity in Bartter's syndrome
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