Evidence for lipid peroxidation during the calcium paradox in vitamin E-deficient rat heart.

Vitamin E is known to play an important role in the protective capacity of tissues as a free radical scavenger. Rats were made deficient in vitamin E, in order to demonstrate more clearly the formation of free radicals after exposing the rat heart to sudden changes in calcium homeostasis. The formation of malondialdehyde was taken as measure for lipid peroxidation. Malondialdehyde was detected in appreciable amounts both in heart tissue and coronary perfusate of vitamin E-deficient rat hearts after exposing them to the sudden changes in calcium concentration as seen during the calcium paradox. These findings emphasize a the hearts of normally fed rats no malondialdehyde could be detected in tissue or coronary perfusate after the calcium paradox. Therefore an essential role for vitamin E against oxidative stress in heart tissue is also indicated.