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The effect of the anabolic hormone 19-nortestosterone propionate (Superanabolon Spofa) on the metabolism of chronically ischaemic striated muscle (anterior tibial m.) was studied in a described model in the rat. Metabolic changes were estimated in terms of the activities of a number of enzymes in muscle fibres. Enzyme activities (AcP, ATPase, CE, LDH, MDH) were determined both biochemically and histochemically excepting SDH, which was determined only by the histochemical way. Morphological changes were investigated by routine histology. Administration of 19-nortestosterone propionate prevented enzymatic changes which are typical for chronic ischaemia, primarily the decrease in the activities of dehydrogenases of Krebs' cycle tricarboxylic acides (MDH, SDH). In addition, the ratio of red to white muscle fibres increased. Administration of anabolic hormone has a similar favourable action on ischaemic muscle as training, studied previously.

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The uptake of emulsified labeled lipids by rat heart mitochondria was studied. Divalent cations greatly stimulated uptake of cholesterol in emulsions containing phospholipids; the effect increased with increasing atomic number. Epinephrine and norepinephrine were also stimulatory. Lipid‐depleted mitochondria were less effective in taking up cholesterol unless lecithin or serum lipids were included in the emulsion. Addition of iodoacetamide did not inhibit uptake, while use of heated mitochondria or extremes of pH augmented lipid uptake. Thus the process appears to be non‐enzymatic. While lecithin emulsions showed no visible change on addition of calcium ions, phosphatidylethanolamine emulsions became turbid and the turbidity was largely removed by addition of heparin. Heparin as well as chondroitin sulfate B and nonionic detergent did inhibit lipid uptake by mitochondria. The possible role of such nonenzymatic lipid uptake in membrane formation and cholesterol accumulation is discussed.

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