Racial Variation in ACE--Genetic and Physiologic Bases
To determine whether differences in the activity of the renin-angiotensin and bradykinin systems are involved in the pathogenesis of blood pressure variation in African Americans.
Each year, more than 40,000 new patients require treatment for end stage renal disease, a condition which is 4-fold higher among African Americans than Caucasians. Trials of angiotensin converting enzyme inhibitors (ACEIs) in Caucasians support a role of the renin-angiotensin system in the pathogenesis of glomerulosclerosis. Yet, despite the high prevalence of nephropathy among African Americans, Blacks have been under-represented in studies in ACEIs. Data from our laboratory suggest that the renal effects of ACEI may differ in African Americans. African Americans are resistant to the anti-hypertensive effects of ACEI and, thus, may be resistant to the renoprotective effects as well. The ACE deletion allele, a variant associated with increased ACE activity and progression of renal diseases, is increased in frequency in African Americans, while the frequency of the Ang AT1 receptor C allele, a variant associated with antihypertensive responsiveness to ACEI is decreased. Moreover, African Americans exhibit decreased sensitivity to Ang I and increased sensitivity to bradykinin. Taken together, these data suggest the hypothesis that ACE activity is increased in African Americans, leading to decreased bradykinin levels ( and receptor sensitization) and increased tissue Ang II (and receptor desensitization).
The study tests the hypothesis that ACE activity is increased in African Americans, leading to decreased bradykinin levels (and receptor sensitization) and increased tissue Ang II (and receptor desensitization). The effects of race, hypertension and ACE insertion/deletion genotype on ACE activity will be determined, as measured by the pressor and renal vasoconstrictor responses to Ang I and Ang II and the vasodilator response to bradykinin. Specific bradykinin and angiotensin receptor antagonists will be used to determine the relative contribution of increased bradykinin and decreased angiotensin II to the renal hemodynamic effects of ACEIs in African Americans and Caucasians.
Observational Model: Defined Population
National Heart, Lung, and Blood Institute (NHLBI)
Results (where available)
- Source: http://clinicaltrials.gov/show/NCT00005757
- Information obtained from ClinicalTrials.gov on July 15, 2010
Human immunodeficiency virus (HIV) infection has been associated with a variety of cardiovascular diseases. Even most industrialised countries exhibit a growing and aging population of HIV...
To develop a comprehensive protocol for assessing cardiovascular reactivity to stressors, for use in epidemiological and clinical investigations of cardiovascular diseases in healthy popul...
The incidence of cardiovascular diseases is still high and further efforts should be done in primary prevention. The main objective is to quantify the burden of subclinical atherosclerosis...
To identify the early emergence and stability of children's hostile behaviors and their associated psychophysiological responses to behavioral challenges, which are possible risk factors...
To extend mortality followup through 25 years for two cohorts of men in the Multiple Risk Factor intervention Trial (MRFIT): the 361,662 men screened and the 12,866 men randomized, and to ...
Following the introduction of antibiotic therapy and widespread inoculations, cardiovascular diseases have leapt ahead of infectious diseases in terms of prevalence in much of the developed and develo...
Cardiovascular diseases are one of the most common causes of death in humans and are responsible for billions of dollars in health care expenditures. As the molecular basis of cardiac diseases continu...
Cardiovascular Diseases (CVD) are the leading cause of death in Brazil.
Cardiovascular diseases are among the most important sources of mortality and morbidity, and have a high disease burden. There are some major well-known risk factors, which contribute to the developme...
Each year, some 30 percent of global deaths are caused by cardiovascular diseases. This figure is worsening due to both the increasing elderly population and severe shortages of medical personnel. The...
Medical and Biotech [MESH] Definitions
Pathological conditions involving the CARDIOVASCULAR SYSTEM including the HEART; the BLOOD VESSELS; or the PERICARDIUM.
Methods and procedures for the diagnosis of diseases or dysfunction of the cardiovascular system or its organs or demonstration of their physiological processes.
Unexpected rapid natural death due to cardiovascular collapse within one hour of initial symptoms. It is usually caused by the worsening of existing heart diseases. The sudden onset of symptoms, such as CHEST PAIN and CARDIAC ARRHYTHMIAS, particularly VENTRICULAR TACHYCARDIA, can lead to the loss of consciousness and cardiac arrest followed by biological death. (from Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 7th ed., 2005)
Processes and properties of the CARDIOVASCULAR SYSTEM as a whole or of any of its parts.
Dental care for patients with chronic diseases. These diseases include chronic cardiovascular, endocrinologic, hematologic, immunologic, neoplastic, and renal diseases. The concept does not include dental care for the mentally or physically disabled which is DENTAL CARE FOR DISABLED.