Isolation of mitochondria from tissues and cells by differential centrifugation.

Differential centrifugation is used to prepare a "heavy" mitochondrial fraction from liver. These mitochondria are relatively pure, highly coupled, and suitable for respiratory studies. This unit presents protocols for isolation of beef heart mitochondria (also suitable for respiratory studies), skeletal muscle mitochondria, and mitochondria from cultured cells can also be isolated from homogenates by differential centrifugation. Differential centrifugation, which separates cellular organelles based on sedimentation velocity, is a rapid method for preparing mitochondria for metabolic studies.