Endothelial function and endothelial nitric oxide synthase intron 4a/b polymorphism in primary hyperparathyroidism

Abstract

Background and aim: Patients with symptomatic primary hyperparathyroidism (pHT) have increased cardiovascular morbidity and mortality. Endothelial nitric oxide synthase (eNOS) intron 4a/b polymorphism is associated with coronary artery disease and hypertension in various populations. Our aim is to evaluate endothelial function in patients with pHT during pre-operative hypercalcemic and postoperative normocalcemic periods and to determine whether intron 4a/b polymorphism of eNOS gene influences endothelial function. Subjects and Methods: Forty patients with pHT (age 48.48 +/- 11.64 yr) were examined pre-operatively and re-examined 5.8 +/- 1.9 months after parathyroidectomy. Forty-three healthy subjects (age 47.13 +/- 8.14 yr) were served as control group. Endothelial function was determined by flow-mediated dilation of brachial artery (FMD). eNOS4a/b polymorphism was detected by polymerase chain reaction. Results: FMD was significantly lower in patients pre-operatively compared with controls (8.48 +/- 1.78% vs 19.49 +/- 2.34%, p2.47 mmol/l) and PTH concentrations (>7.75 pmol/l) were significant independent predictors of lower FMD (<16.7%). ENOS4a/b polymorphism did not enter in this model. Conclusion: Impaired endothelial function in patients with pHT improves after successful parathyroid surgery. No compelling data are evident to suggest that eNOS4a/b polymorphism modifies the endothelial function in patients with pHT. (J. Endocrinol. Invest. 32: 611-616, 2009) (C) 2009, Editrice Kurtis