Because of the molecular configuration, most free radicals are highly reactive and
can cause cell injury. Protective mechanisms have evolved to provide defense against
free-radical injury. Any time these defense systems are overwhelmed, such as during
disease states, cell dysfunction may occur. In this review we discuss cellular sources
as well as the significance of free radicals, oxidative stress, and antioxidants.
A probable role of oxidative stress in various cardiac pathologies has been also analyzed.
Although some methods for the detection of free radicals as well as oxidative stress
have been cited, better methods to study the quantity as well as subcellular distribution
of free radicals are needed in order to understand fully the role of free radicals
in both health and disease.