Research article

Adenosine infusion increases plasma levels of VEGF in humans

Thomas H Adair^1,2 , Reid Cotten^1,3 , Jian-Wei Gu^1,2 , Janelle S Pryor^1,2 , Kenneth R Bennett^1,3 , Michael R McMullan^1,3 , Preston McDonnell^1,2 and Jean-Pierre Montani^1,4

¹Angiogenesis Research LaboratoriesCenter for Excellence in Cardiovascular-Renal Research

²Department of Physiology & Biophysics University of Mississippi Medical Center Jackson, MS 39216, USA

³Department of Medicine University of Mississippi Medical Center Jackson, MS 39216, USA

⁴Institute of PhysiologyUniversity of Fribourg, 1700 Fribourg, Switzerland

author email corresponding author email

BMC Physiology 2005, 5:10doi:10.1186/1472-6793-5-10

Published:	20 June 2005

Abstract

Background

Many in vitro studies have shown that adenosine (Ado) can induce vascular endothelial growth factor (VEGF) mRNA and protein expression and stimulate endothelial proliferation. In the present study, we seek to determine whether Ado can increase circulating levels of VEGF protein in the intact human.

Methods

Five outpatients 49.3 ± 6.7 years of age and weighing 88.2 ± 8.5 kg were selected. They were given a 6 min intravenous infusion of Ado (0.14 mg kg^-1 min^-1) in conjunction with sestamibi myocardial perfusion scans. Mean blood pressure (MBP, calculated from systolic and diastolic values) and heart rate (HR) were determined before Ado infusion and every 2 min for the next 10 min. Plasma VEGF concentrations (ELISA) were determined immediately before Ado infusion and 1 h, 2 h, and 8 h after the infusion.

Results

Plasma VEGF concentration averaged 20.3 ± 2.0 pg ml^-1 prior to Ado infusion, and increased to 62.7 ± 18.1 pg ml^-1 at 1 h post- infusion (p < 0.01). VEGF plasma concentration returned to basal levels 2 h after infusion (23.3 ± 3.4 pg ml^-1). MBP averaged 116 ± 7 mmHg and heart rate averaged 70 ± 7 prior to Ado infusion. MBP decreased by a maximum of ~22% and HR increased by a maximum of ~17% during the infusion.

Conclusion

We conclude from these preliminary findings that intravenous infusion of adenosine can increase plasma levels of VEGF in humans.