[Characteristics of the effect of 2-pyrrolidone acetamide (piracetam) on energy coupling in rat skeletal muscle mitochondria during cold stress].

Effects of 2-pyrrolidone acetamide (piracetam) on energetic state of mitochondria were studied in skeletal muscles of intact and ovaryectomized rats under conditions of drastic cooling (4 min swimming at 10 degrees). Readministration of piracetam was shown to cause uncoupling of oxidation and phosphorylation in mitochondrial respiratory chain (a decrease in respiratory control by Chance), as well as the drug increased the rate of O2 consumption in presence of oligomycin and decreased the uncoupler stimulating action on respiration in the group of intact animals. The alterations observed were most distinct in rats with cold stress, which was followed by piracetam administration, except of the rate of respiration stimulation, distinctly increased in presence of uncoupler. Piracetam did not exhibit any noticeable effects on the patterns of respiration studied in skeletal muscles of ovaryectomized rats. Protective properties of piracetam in cooling are discussed.