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M Hillar

Publications and source records attributed to M Hillar.

27 records · Page 2Linked to original sources

Studies on a rat liver subcellular poly A-rich RNA fraction with glutamate dehydrogenase template activity.

A heterogeneous poly A-mRNA fraction was isolated from rat liver microsomes by phenol:chloroform extraction, millipore filtration, and poly U-agarose affinity chromatography. The fractions were characterized by their secondary structures and poly A contents. From translational studies, the isolated fraction was found to have high glutamate dehydrogenase template activity in cell-free systems containing microsomes or polysomes. A spectrophotometric procedure for following enzyme biosynthesis was also developed.

Animals↗

Hormonal induction of glutamate dehydrogenase in rat liver.

Glutamate dehydrogenase rapidly increases in microsomes and appears in the cytoplasm after administration of cortisone, cAMP, hydrocortisone-acetate. Prolonged administration of ACTH maintains high level of enzyme in the mitochondria and microsomes. Hydrocortisone-acetate, insulin and cortisone decrease drastically enzyme in mitochondria.

Adrenocorticotropic Hormone↗

Correlation of the effects of citric acid cycle metabolites on succinate oxidation by rat liver mitochondria and submitochondrial particles.

1. Succinate dehydrogenase is inhibited by citrate and beta-hydroxy-butyrate in a complex manner, both in mitochondria and submitochondrial particles. Kinetics of inhibition in the particles points to a competitive component in the mechanism involved. 2. Pyruvate, alpha-ketoglutarate, malate, and glutamate stimulate oxidation of succinate by mitochondria. 3. Stimulation by alpha-ketoglutarate and glutamate is not influenced by the presence of rotenone. 4. Stimulation by pyruvate is higher in the absence of rotenone and increases significantly in the presence of K+ and valinomycin. Pyruvate supplies in mitochondria reducing equivalents for malate dehydrogenase operating in the reverse direction-reduction of oxaloacetate to malate. 5. Stimulation by malate is higher in the presence of rotenone.

Animals↗