Measurement of Free Radicals from Smoke Inhalation and Oxygen Exposure by Spin Trapping and Esr Spectroscopy

Abstract

Research in smoke inhalation has established that free radicals are produced from gases released during combustion and these species impair lung function. Using spin traps and their adducts in an animal model free radicals were measured. Various hyperbaric oxygen regimens were tested in an attempt to attenuate pulmonary damage caused by free radical reactions. Our data demonstrated that persistent oxygen- and carbon-centered free radicals are detectable in intravascular fluids after smoke inhalation. The smoke inhalation model showed however, clearing of spin trap adducts one hour after smoke exposure. Other researchers have found that when 100% oxygen is given at 1 atmosphere absolute (ATA) for 1 h, free radicals were not detectable. However, oxygen given at 2.5 ATA does produce detectable free radicals. With continued exposure at this pressure, the levels of free radicals increase for up to 60 min. This study suggests that the level of free radical induced oxygen toxicity may be a function of oxygen pressure and duration of oxygen exposure.

Influence of an Orally Effective SOD on Hyperbaric Oxygen-related Cell Damage

“…Exposure to HBO leads to excess formation of oxygen radicals, both in vitro [14 -16] as well as in vivo [2,17] and induces DNA single strand-breaks in cell cultures [18,19] and in blood cells of test subjects. [1,3,10,20] In these studies as well as in the present one, DNA single strand breaks were quantified using the alkaline single cell gel electrophoresis assay ("comet assay"), which allows the detection of DNA single strand-breaks, incomplete excision repair sites and alkali labile sites.…”

Microarray Analysis of Gene Expression in Rat Cortical Neurons Exposed to Hyperbaric Air and Oxygen

“…However, substantial direct and indirect evidence indicates that normobaric and hyperbaric hyperoxia induce accumulation of reactive oxygen species (ROS), such as superoxide, singlet oxygen, hydrogen peroxide and hydroxyl radicals in vitro and in vivo [3][4][5][6][7][8][9]. The imbalance between ROS accumulation and inactivation results in oxidative stress, glutathione depletion, oxidationinduced DNA damage, as well as lipid and protein modification.…”

Free Radicals and Medicine

“…Smoke inhalation by rabbits formed unidentified PBN radical adducts in plasma (Yamaguchi et al‚ 1992;Murphy et al‚ 1991). Cotton smoke formed radical adduct concentrations similar to those caused by 2.5 atm of oxygen (Yamaguchi et al‚ 1992). Formation of a burst of PBN radical adducts by a brief exposure to cigarette smoke required pretreatment by bacterial endotoxin (Murphy et al‚ 1991).…”

“…Both the in vitro effects of this smoke and the use of ESR in these studies have been extensively reviewed (Pryor 1992). Smoke inhalation by rabbits formed unidentified PBN radical adducts in plasma (Yamaguchi et al‚ 1992;Murphy et al‚ 1991). Cotton smoke formed radical adduct concentrations similar to those caused by 2.5 atm of oxygen (Yamaguchi et al‚ 1992).…”