Background: Most evidence currently favours a fundamental role of the autonomic nervous system in the pathogenesis of essential hypertension. Recent studies suggest that about 40% of baroreflex variation, an index of cardiac autonomic control, is influenced by genetic factors.
Methods and results: The aim of this study was to investigate the effect of a common polymorphic variant of the bradykinin B2 receptor gene (B2R; -58T/C) on the autonomic regulation of baroreflex sensitivity (BRS) in 129 mild-moderate never-treated hypertensive patients. No significant differences were found for clinical and biochemical parameters among genotypes. BRS increased with the number of B2R T alleles. B2R genotype was a strong independent predictor of BRS, accounting for 12% of its variation. We suggest that a decrease in the transcription of the bradykinin B2R gene in the presence of the B2R -58C allele could reduce BRS via the diminished effect of bradykinin.
Conclusions: B2R genotype can explain part of the BRS variation that is unaccounted for by simple anthropometric variables and common risk factors.