Post-Exercise
Decrease of Plasma Hyaluronan: Increased
Clearance or Diminished Production?
H.
G. HINGHOFER-SZALKAY1,2 , W. MEKONEN2,
A. RÖSSLER1, G. SCHWABERGER1,
M. LAMPRECHT3, P. HOFMANN3
1Department of
Physiology, School of Medicine,
Karl-Franzens-University, 2Institute
for Adaptive and Spaceflight Physiology, Austrian
Society for Aerospace Medicine and 3Institut
für Sportwissenschaften,
Karl-Franzens-University, Graz, Austria
Received April 10, 2001
Accepted July 19, 2001
Summary
The exercise-induced increase and
post-exercise decrease of plasma hyaluronan
concentration were studied in human subjects. Six
well trained men performed incremental exercise
until exhaustion (MAX), intensive (submaximal,
SUB) and extensive exercise (moderate, MOD) on a
bicycle ergometer, defined as work at 100, 77 and
50 % of maximal oxygen consumption. Hyaluronan
was analyzed using a high-sensitivity,
proteoglycan-dependent time-resolved immunoassay
and hemoglobin, hematocrit and plasma protein
levels were assessed using standard laboratory
procedures. Compared to resting control levels,
the plasma hyaluronan concentration (pHA)
increased (p<0.05) by 76 % (65.0±6.1 vs.
37.0±1.0 µg/l) during 15 min MAX, by 44%
(56.4±2.6 vs. 39.2±3.8 µg/l) during 30 min SUB
and by 27 % (46.3±7.8 vs. 36.4±4.3 µg/l)
during 90 min MOD. The increase with time
averaged 4.03 %.min-1 during MAX, 1.35%.min-1
during SUB and 0.35 %.min-1 during MOD. After
exercise (15 and 30 min), pHA decreased by 43 %
below resting levels after MAX (p<0.05) and by
36 % after SUB, respectively. In conclusion, pHA
steadily rose with time during physical exertion,
with a non-linear increase of concentration/time
slope with exercise intensity; second, the
magnitude of the post-exercise pHA decrease was
proportional to the exercise-induced pHA
increase, suggesting elevated hyaluronan
clearance with rising plasma levels after
physical exertion..
Key
words
Hyaluronan
· Hyaluronic acid · Lymph flow · Physical
exercise · Plasma volume
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H. G. Hinghofer-Szalkay, Department of
Physiology, Karl-Franzens-University Graz,
Harrachgasse 21, 8010 Graz, Austria. Tel:
+43-316-383638. Fax: +43-316-381270. Email: helmut.hinghofer@kfunigraz.ac.at
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