ORIGINAL PAPER
Exercise h-FABP plasma concentration in healthy subjects

Submitted: 11 October 2005
Accepted: 23 November 2005

Corresponding author:
Łukasz A. Małek, MD
1st Department of Cardiology
Medical University of Warsaw
Central University Hospital
Banacha 1a
02-097 Warsaw, Poland
Phone: +48 22 599 64 11
Fax: +48 22 822 74 96
E-mail: lamalek@amwaw.edu.pl

Introduction
Heart fatty acid binding protein (h-FABP) is considered a heart specific protein which binds fatty acids (FABP) within the cardiac muscle cells [1]. It has been reported as an early marker of myocardial ischemia with sensitivity >80% in detecting acute myocardial infarction (AMI) within 30-210 minutes after the symptom onset [2]. It usually peaks after 6h and returns to baseline values after 24h. Although the cardiac tissue contains a 0.5 mg/g wet weight of the h-FABP, the protein is also present in the skeletal muscles in concentrations varying between 0.05 and 0.2 mg/g wet weight of tissue [3, 4].
Physical exercise may influence plasma concentrations of biochemical markers in healthy subjects. In one study the h-FABP concentrations were measured using the quantity one-step immunosorbent assay (sandwich ELISA) in six healthy men after 20 minutes of down-hill running. Mean h-FABP concentrations were significantly elevated beginning from 30 minutes after running (13.9 fold increase of the initial mean concentration 3 µg/l) [5]. In another study h-FABP concentrations were measured after acute and chronic exercise in a group of 14 junior rowers using the same ELISA sandwich method [6]. The percentage increase in h-FABP immediately after training was 78% after a time trial for 4 km and up to 362% after a steady state rowing for 12-14 km followed by weight training. When the chronic effect of exercise was studied, the baseline h-FABP levels were independent of previous training.
The normal ranges of the h-FABP plasma concentrations vary between 0 and 5 µg/l [7, 8]. The cut-off point for h-FABP in detecting AMI within 6 hours of the onset of chest pain with almost 81.8% sensitivity and 86.4% specificity was reported to be >12 µg/l [9]. Recently a new point-of-care test for measuring of h-FABP with a cut-off point of 7 µg/l was introduced. Knowing that the h-FABP plasma concentrations increase after an exercise and that the point-of-care test cut-off points are lower than those reported for the AMI we wanted to...


View full text...