[Effect of tetracycline on rat liver mitochondrial oxidative phosphorylation in vivo and in vitro under a varying body allowance of protein].

An investigation of the tetracycline action in vivo and in vitro showed it to reduce the rate of oxidative phosphorylation in the rat liver mitochondria which, with an increased concentration or a longer introduction of the drug, gives place to inhibition of respiration. These changes occur following introduction of 100 mg/kg by the 10th day of the experiment and of 20 mg/kg--by the 20th day. The protein-low background is a factor contributing to a speedier effect of tetracycline. Heat-treated tetracycline produces greater changes than does the native drug.