Intentionality and free-will: the crucial effects of neuronal networks on human evolution

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Differential Effects of Rotenone and Amytal on Mitochondrial Electron and Energy Transfer

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OXIDATION OF CHOLINE IN RAT LIVER MITOCHONDRIA.

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Ion Transport in Liver Mitochondria IV. THE RELATIONSHIP BETWEEN ION TRANSLOCATION AND ELECTRON TRANSPORT

Abstract Addition of small amounts of Ca++ to liver mitochondria incubated in the absence of phosphate or acetate results in an inhibition of respiration. The inhibition of respiration is reversed by increasing the concentration of substrate anions in the medium, and is enhanced by increasing the ionic strength or the pH of the medium. The H+:O and Ca++:O ratios are increased severalfold when measured under conditions of inhibited respiration. Furthermore, mitochondria which have entered a state of inhibited respiration continue to take up Ca++ and to release H+. It is concluded that the above stoichiometries in the absence of phosphate or acetate are determined by both uninhibited and inhibited respirations. The higher the concentration of Ca++, the larger is the contribution of the inhibited respiration. In the presence of acetate, the Ca++ to total oxygen ratio is in the region of 2.0 to 2.5 with succinate as substrate. The inhibition of respiration is related to the increase of the intramitochondrial pH as followed kinetically with the bromthymol blue technique. The bromthymol blue response is dependent on the rate of influx of anions. Increasing the ionic strength and pH enhances the bromthymol blue response, presumably by restraining the influx of anions. The mechanism by which the inhibition of respiration causes the superstoichiometric ratios is discussed

Ion transport in liver mitochondria. I. Metabolism-independent Ca++ binding and H+ release.

Abstract 1. Liver mitochondria are able to bind large amounts of Ca++ through a process which is independent of metabolism. The amount of Ca++ bound is increased by increasing the pH of the medium and is decreased by the addition of univalent cations. The binding of Ca++ to the mitochondria is a function of the concentration of Ca++ in the medium and is affected by the Ca++ to protein ratio. 2. A large part of the metabolism-independent binding of Ca++ occurs in a space which is rendered accessible to univalent cations by valinomycin or gramicidin. In fact when the mitochondria are pretreated with valinomycin or gramicidin, the binding of Ca++ is increased in a sucrose medium and decreased in a KCl or NaCl medium. The competition between Ca++ and univalent cations has been studied. 3. The metabolism-independent binding of Ca++ is coupled to a release of H+ or of K+. The conditions affecting the exchange between divalent and univalent cations are studied and data are reported on the stoichiometry of H+:Ca++ and K+:Ca++ in normal and valinomycin-treated mitochondria

Succinate-linked Acetoacetate Reduction: II. ELECTRON TRANSFER PATHWAY AND ENERGY REQUIREMENT

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