Abstract
Ionizing 60Co gamma-radiation used in radiotherapy belongs to main exogenous sources of free radicals, which can cause damage to healthy biomolecules and tissues. Free radicals are characterized by unpaired electrons.
In the presence of oxygen, a molecule of oxygen is immediately bound instead of the unpaired electron, thus producing a peroxylic radical, which tends to get the missing elektron from the another compound with forming the other free radical. This chain reaction is discontinued either by a bond of two radicals one to another or by a reaction with an antioxidant.
After depletion of the anti-oxidative protection, the ratio between reduced and oxidized glutathione in cells, which is a sensitive parameter of the oxidative stress, decreases. Therapeutic lasers demonstrably affect cell organelles, membrane channels, nociceptors, mediators and cytokines.
In clinical medicine, there are obvious analgesic anti-inflammatory and immunostimulating effects and also effects on healing of wounds.