Studies of isolated rat liver mitochondria were undertaken in order to evaluate the importance of glutamate transport, oxidation reduction state, and product inhibition on the rates of formation of ammonia from glutamate. Uptake and efflux of glutamate across the mitochondrial membrane were measured isotopically in the presence of rotenone. Efflux was stimulated by H+ in the mitochondrial matri...

Studies of isolated rat liver mitochondria were undertaken in order to evaluate the importance of glutama te transport, oxidation reduction state, and product inhibition on the rates of formation of ammonia from glutamate. Uptake and efflux of glutamate across the mitochondrial membrane were measured isotopically in the presence of rotenone. Efflux was stimulated by H+ in the mitochondrial matr...

Changes in the morphology of rat liver mitochondria brought about by different methods of isolation and the concomitant changes in ATP-ase activity were studied. The morphology was investigated with the electron microscope. It was found that the ATP-ase activity of the isolated mitochondria cannot be readily correlated with the morphology of the mitochondria. The ATP-ase found in these preparat...

Background: The accumulation of calcium by mitochondria regulates cell survival. Results: Purified mitochondria exhibit increased calcium uptake in the presence of NMDA receptor agonists. Conclusion: Functional NMDA-like receptors may be present on mitochondria. Significance: Learning how NMDA facilitates mitochondrial calcium uptake provides a new dimension to the understanding of cellular hom...

The effects of several rotenoids have been studied on potato (Solanum tuberosum L.) tuber and etiolated mung bean (Phaseolus aureus Roxb.) hypocotyls mitochondria. The selective inhibition of mitochondrial complex I is characterized by several tests: (a) no effect can be observed on exogenous NADH or succinate oxidation; (b) malate oxidation is inhibited at pH 7.5; (c) one-third decrease of ADP...

Angular light-scattering studies have been carried out on suspensions of isolated rat liver mitochondria. The angular scatter pattern has a large forward component, typical of large particles. Changes in dissymmetry and in the intensity of light scattered at 90 degrees have been correlated with changes in optical density during the course of mitochondrial swelling and contraction. Such changes ...

Erythropoietin (Ep), insulin, and prostaglandins E1 and A1 (PGE1, PGA1) enhanced heme synthesis by mitochondria isolated from embryonic and adult mouse liver cells. The combination of Ep with PGE1 had an antagonistic effect, while that of Ep with PGA1 gave an additive result. The capability of isolated human platelet mitochondria to synthesize heme was also shown. This activity was stimulated b...

1. The present paper constitutes a preliminary study of the morphology of mitochondria by means of electron microscopy. 2. The mitochondria that were the subject of this investigation were obtained from a lymphosarcoma of the rat. They were separated from the other components of the leukemic cells by a method of differential centrifugation, and thus made available for direct examination in the ...

1. [14C]Malonyl-CoA bound to intact mitochondria isolated from rat liver and heart in a manner consistent with the presence of two independent classes of binding sites in each tissue. 2. The binding characteristics for mitochondria obtained from fed male rats were: for heart, KD(1) = 1 -l8 nM, KD(2) = 30uM, N1 = 7pmol/mg of protein, N2 = approx. 660pmol/mg of protein; for liver, KD(1) = 0.1 M, ...

Mitochondrial fractions, relatively free from contsmination by other cytopla-~mic structures, have been isolated by differential centrifugation from homogenates of brown adipose tissue from starved rats. It was possible in such fractions to distinguish two types of mitochondria in this tissue. Type I mitochondria, when morphologically intact, are limited by a bilaminar membrane and show regular...