Heart Rate Performance Curve And Arg389gly ß 1–adrenoceptor Polymorphism

Abstract

Differences in ß 1-adrenoceptor (AR) sensitivity were described to explain different response patterns of the Heart Rate Performance Curve (HRPC) (MSSE 33, 2001, 5: S202). PURPOSE The purpose of the study was to investigate if the Arg389Gly ß 1- adrenoceptor polymorphism is related to different patterns of the HRPC. METHODS 164 young healthy male sports students participated in the study. Incremental cycle ergometer exercise (40 W start, 20W/min increase) was performed in all subjects to obtain the heart rate performance (HRPC) and to determine the different HR patterns by means of the degree and the direction of deflection (kHR) of the HRPC. The ß 1-adrenoceptor Arg389Gly polymorphism was determined from venous blood samples according to published standards. ANOVA was calculated to describe differences of kHR between the three genetic variants. RESULTS The number of subjects presenting different variants was 83 (AA), 73 (AG) and 8 (GG). kHR was found at 0.29±0.34 (AA), 0.37±0.36 (AG) and 0.37±0.37 (GG). No significant difference was found for kHR between the different polymorphisms, however a trend to lower values in the AA variant was found. CONCLUSION As previously reported the Arg389Gly ß 1-AR polymorphism had no significant functional relationship with HR response to incremental cycle ergometer exercise in young healthy male subjects.