Acetoin metabolism in animal tissues

The acetoin-synthesizing activity has been studied in the skeletal muscles, brain, liver and spleen homogenates (numbered as the activity decreases). The acetoin-synthesizing activity drastically increases in case of the acetaldehyde excess and alcohol intoxication. The acetaldehyde concentrations of above 1.10(-3) M inhibit the liver pyruvate dehydrogenase activity and increase the non-oxidative transformation of pyruvate. Acetoin is rapidly metabolized in the organism eliminating from blood 10 minutes after its injection. Acetoin is an effective precursor in the biosynthesis of lipids.     

Endogenous ouabain-like substances in animal tissues

Methods of purification and properties of the digitalis-like substances from different animal-origin sources are considered. Possible mechanisms of the cardiac glycoside-effect on the cardiac muscle and endogenous digitalis-like factors' effect on the smooth muscles of the blood vessels are discussed. Criteria that may be used to characterize the digitalis-like activity in samples and extracts obtained from different tissues are presented. The role of these substances in some types of pathologies, especially in the development of hypertension, is considered.