The Response of Na+/K+-ATPase
of Human Erythrocytes to Green Laser Light Treatment
P. KAŠŠÁK, L. ŠIKUROVÁ, P. KVASNIČKA, M.
Division of Biomedical Physics, Faculty of Mathematics, Physics,
and Computer Science, Comenius University, Bratislava, Slovak
Republic and 1Department of General Biophysics, University of
Lodz, Łódź, Poland
Received September 30, 2004
Accepted April 4, 2005
On-line available May 24, 2005
The objective of this study was to investigate the response of
Na+/K+-ATPase of human erythrocytes to
green laser irradiation. Effects of green laser light of
fluences 9.5-63.3 J.cm-2 and merocyanine 540-mediated laser
light treatment were studied. Isolated erythrocyte membranes
(protein concentration of 1 mg/ml) were irradiated by Nd:YAG
laser (532 nm, 30 mW) and then incubated in a medium with 2 mM
ATP for 30 min. Activity of ATPase was determined
colorimetrically by measuring the colored reaction product of
liberated inorganic phosphate and malachite green at 640 nm.
Contribution of Na+/K+-ATPase to overall
phosphate production was determined using ouabain. A positive
effect of green laser light on Na+/K+-ATPase
activity was observed. The dependence of enzymatically liberated
inorganic phosphate on light fluence showed a linear correlation
(R2=0.96, P=0.0005) for all fluences applied (9.5-63.3 J.cm-2).
On the other hand, MC 540-mediated phototreatment caused a
suppression of enzyme activity.
Na+/K+-ATPase activity • Biostimulation •
Erythrocyte membrane • Merocyanine 540 • Photodynamic processes