1. We have investigated the effects of ethanethiol, methanethiol and dimethyl sulphide on some metabolic processes of isolated rat hepatocytes, isolated mitochondria from liver and brain and ox-heart submitochondrial particles. 2. Ethanethiol, but not dimethyl sulphide, inhibited both gluconeogenesis and ureogenesis from various substrates in rat hepatocytes, depressed cellular ATP content and ...

Epigallocatechin gallate (EGCG) is a green tea antioxidant with adverse effects on rat liver mitochondria and hepatocytes at high doses. Here, we assessed whether low doses of EGCG would protect these systems from damage induced by tert-butyl hydroperoxide (tBHP). Rat liver mitochondria or permeabilized rat hepatocytes were pretreated with EGCG and then exposed to tBHP. Oxygen consumption, mito...

Intact mitochondria, isolated from regenerating rat liver 2-3 days after partial hepatectomy, are 2.5-3 times more active in amino acid incorporation than mitochondria from control livers. Liver mitochondria from sham-operated animals showed normal amounts of incorporation. Sterile procedures insured low levels of bacterial contamination; cycloheximide was used to eliminate any contribution by ...

It has been reported that the mouse and the rat are susceptible to the action of plague murine toxin, whereas the rabbit is not (1). The effect of this toxin on mitochondrial respiration varies with respect to the animal species and organ from which the mitochondria are isolated. The respiration of rat heart (1) as well as rat and rabbit liver mitochondria (2) is inhibited by the toxin. In cont...

Resistive particle counting has been developed for the accurate sizing and counting of mitochondria in solution. The normal detection limit with a 30 micro aperture is 0.48 micro diameter, or 0.056 micro(3) particle volume The mean volume of rat liver mitochondria was 0.42 micro(3) or 0.93 micro in diameter. The average value for numbers of particles per milligram of mitochondrial protein was 4...

The objective of the present work was to investigate the mechanism of alloxan-induced Ca2+ release from rat liver mitochondria. Transport of Ca2+, oxidation and hydrolysis of mitochondrial pyridine nucleotides, changes in the mitochondrial membrane potential, and oxygen consumption by mitochondria were investigated. Alloxan does not inhibit the uptake of Ca2+ but stimulates the release of Ca2+ ...

Mitochondria cannot maximize energy production, efficiency, and the cellular ATP phosphorylation potential all at the same time. The theoretical and observed determinations of coupling of oxidative phosphorylation in mitochondria from rat liver, heart, and brain were compared using classical and nonequilibrium thermodynamic measures. Additionally, the optimal thermodynamic efficiency and flow r...

The regulatory properties of the Ca2+-sensitive intramitochondrial enzymes (pyruvate dehydrogenase phosphate phosphatase, NAD+-isocitrate dehydrogenase and 2-oxoglutarate dehydrogenase) in extracts of rat liver mitochondria appeared to be essentially similar to those described previously for other mammalian tissues. In particular, the enzymes were activated severalfold by Ca2+, with half-maxima...

SUMMARY The concanavalin A (con A)-binding capacity of mito chondria isolated by sucrose density gradient methods from host livers, from Morris hepatomas 7800 and 7777, and from mouse myeloma MOPC-46 were compared. con A binding to the various mitochondrial preparations was quantitated using an isotopic assay procedure in which con A-acetyl-3H is used and by a spectrophotometric ag glutination ...