Objective: Insertion (I)/deletion (D) polymorphisms in the angiotensin-converting enzyme (ACE) gene have the potential to serve as a marker for an increased risk of cardiovascular events. Increased plasma levels of human atrial natriuretic polypeptide (ANP) and brain natriuretic polypeptide (BNP) are important indexes of cardiac function. The aim of this study was to examine possible relationships between I/D polymorphisms and the myocardial release of ANP and BNP in Japanese hemodialysis (HD) patients (n=131).
Material and methods: We studied 131 non-diabetic hemodialysis patients. The genotype of ACE gene was determined by polymerase chain reaction with a set of specific timers. ANP and BNP levels were measured before HD.
Results: The plasma levels of ANP and BNP were significantly lower in the DD genotype group compared to those in the II group. Corresponding levels in the ID genotype group were intermediate between those in the DD and II groups. ACE polymorphism was associated with neither ejection fraction nor left ventricular mass/height index (LVMI), as evidenced by echocardiographic findings (n=107). Plasma levels of ANP were significantly correlated with left atrial diameter (LAD) in patients as a whole, but this correlation was only observed in the II genotype group, and not in the DD or ID groups. Plasma levels of BNP were significantly correlated with LAD, left ventricular end systolic diameter and LVMI in patients as a whole, but these correlations were seen only in the II genotype group.
Conclusion: The results suggest that the plasma levels of these natriuretic peptides should be evaluated on the basis of ACE polymorphism for assessing cardiac diseases due to volume overload in Japanese HD patients.