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Increased sensitivity to bradykinin among African Americans
J V Gainer1, J H Nadeau, D Ryder
1Vanderbilt University Medical Center, Division of Clinical Pharmacology, Nashville, TN 37232-6602, USA.
The Journal of Allergy and Clinical Immunology
|August 1, 1996
Summary
African Americans exhibit a heightened wheal response to bradykinin, suggesting racial differences in the kallikrein-kinin system. This may explain their increased risk of angioedema from angiotensin-converting enzyme (ACE) inhibitors.
Area of Science:
- Pharmacology
- Cardiovascular Research
- Human Physiology
Background:
- Angioedema is a serious side effect of angiotensin-converting enzyme (ACE) inhibitors.
- Bradykinin is implicated in angioedema pathogenesis.
- African Americans have a higher risk of ACE inhibitor-associated angioedema compared to Caucasians.
Purpose of the Study:
- To investigate the hypothesis that African Americans have decreased endogenous bradykinin levels, leading to increased sensitivity.
- To compare the wheal response to bradykinin in hypertensive and normotensive African Americans and Caucasians.
Main Methods:
- Intradermal injections of two doses of bradykinin (1 microgram and 10 micrograms) were administered.
- The study employed a randomized, double-blind design.
- Wheal response was measured in salt-replete hypertensive and normotensive participants.
Main Results:
- A higher bradykinin dose was associated with an increased wheal response.
- African American race was significantly associated with an increased wheal response.
- Hypertension was also linked to a greater wheal response to bradykinin.
Conclusions:
- The findings support the existence of racial differences in the kallikrein-kinin system.
- Abnormalities in the tissue kallikrein-kinin system may play a role in essential hypertension.
- This research provides insights into the mechanisms underlying ACE inhibitor-induced angioedema in different racial groups.
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