Study Of Normobaric Hyperoxia Effects During Focal Hypoxia-ischemic Injury In Mice Using Optical Spectroscopy Measurements
Abstract
Optical spectroscopy has seen tremendous growth and development in recent years
and has been extensively used to characterize the optical properties of biological tissues. The
purpose of this study is to investigate the values of oxygen saturation and concentration of
hemoglobin in mice with focal hypoxic ischemia after being recovered in normobaric hyperoxia.
Mice at five different age levels were used for this purpose, in order to see the effects of
hyperoxia at different developmental stages of the brain; ischemia was induced in them by
ligating their right carotid artery and subjecting them to hypoxic (8% oxygen) environment for
half an hour. Mice were then subjected to normobaric hyperoxia (100% oxygen) or room air for
half an hour. The hyperoxia group showed an increase in oxyhemoglobin concentration in all
age groups of mice, also an increase in oxygen saturation was noted in all age groups of mice,
except the P28 group. These results indicate that normobaric hyperoxia increases
oxyhemoglobin concentration in adult mice with focal cerebral ischemia and the extent of
improvement seem to vary with age. This study continues to show the efficiency of optical
spectroscopy in determining tissue optical properties, however one of the drawbacks to this study using needle-like probe was the skin of the animal gave rise to artifacts during
measurements and had to be removed to get better optical readings.