Increased platelet alpha2B-adrenergic receptor gene expression in well-controlled hypertensives: the effect of arterial stiffness

J Am Soc Hypertens. 2017 Nov;11(11):762-768. doi: 10.1016/j.jash.2017.08.006. Epub 2017 Aug 26.

Abstract

Catecholamines play a major role in atherothrombotic mechanisms in essential hypertension. Alpha2B-adrenergic receptors (α2B-ARs) are implicated in the pathophysiology of platelet aggregation. In this study, we evaluated platelet α2B-AR gene expression levels in patients with well-controlled essential hypertension compared with normal individuals and investigated their association with increased arterial stiffness. Fifty-nine patients with well-controlled essential hypertension (34 men, mean age 65 ± 9 years) and 26 normotensives (19 men, mean age 64 ± 8 years) were included in the study. For each patient, carotid-femoral pulse wave velocity (PWV) and carotid-radial PWV were evaluated. In addition, blood samples were obtained and platelets were isolated. The α2B-AR gene expression levels in platelets were examined by real-time polymerase chain reaction for each participant. Well-controlled hypertensive patients showed significantly higher gene expression levels of α2B-Rs in platelets compared with normotensives (34.7 ± 29.5 vs 17.6 ± 12.5, respectively, P = .005). Interestingly, we found that carotid-femoral PWV and carotid-radial PWV were positively correlated with platelet α2B-R gene expression levels (r = 0.59, P < .001, and r = 0.39, P = .002, respectively).Platelet α2B-R gene expression levels are increased in patients with well-controlled essential hypertension compared with normotensives and are correlated with increased PWV in those patients. Our data indicate an association of arterial stiffness and platelet α2B-Rs gene expression and indicate the need for further research.

Keywords: Essential hypertension; pulse wave velocity; thrombosis.

MeSH terms

  • Aged
  • Blood Platelets / metabolism*
  • Blood Pressure / physiology
  • Carotid Arteries / physiopathology
  • Essential Hypertension / drug therapy
  • Essential Hypertension / physiopathology*
  • Female
  • Femoral Artery / physiopathology
  • Humans
  • Male
  • Middle Aged
  • Pulse Wave Analysis
  • Radial Artery / physiopathology
  • Real-Time Polymerase Chain Reaction
  • Receptors, Adrenergic, alpha-2 / metabolism*
  • Vascular Stiffness / physiology*

Substances

  • ADRA2B protein, human
  • Receptors, Adrenergic, alpha-2