THE ENZYMATIC REDUCTION OF TETRAZOLIUM SALTS BY AMINES

1956 ◽  
Vol 34 (1) ◽  
pp. 1095-1106 ◽  
Author(s):  
J. R. Lagnado ◽  
T. L. Sourkes
Keyword(s):  
Rat Brain ◽  
Kinetic Data ◽  
Amine Oxidase ◽  
Enzyme System ◽  
Pig Liver ◽  
Heat Stable ◽  
Rat Brain And Liver ◽  
Enzymatic Reduction ◽  
Reducing Activity ◽  
Cofactor Activity

An enzyme system effecting the dehydrogenation of amines has been detected in rat brain and liver suspensions by the use of tetrazolium dyes as terminal electron acceptors. Kinetic data on this system are presented and the evidence for requirement of a cofactor is described. Thus, after washing or dialysis, rat brain suspensions have a considerably lowered tetrazolium reducing activity, which can be restored by addition of boiled extracts of rat liver, rat brain, pig liver, or baker's yeast. The heat-stable cofactor in pig liver and rat brain which is necessary for the activity of the tetrazolium reducing system is dialyzable. Pig liver extracts lose their cofactor activity on ashing. The nature of the electron transporting system active in amine dehydrogenation is discussed and the properties of the tetrazolium reducing and the amine oxidase systems are compared.

THE ENZYMATIC REDUCTION OF TETRAZOLIUM SALTS BY AMINES

1956 ◽  
Vol 34 (6) ◽  
pp. 1095-1106 ◽  
Author(s):  
J. R. Lagnado ◽  
T. L. Sourkes
Keyword(s):  
Rat Brain ◽  
Kinetic Data ◽  
Amine Oxidase ◽  
Enzyme System ◽  
Pig Liver ◽  
Heat Stable ◽  
Rat Brain And Liver ◽  
Enzymatic Reduction ◽  
Reducing Activity ◽  
Cofactor Activity

An enzyme system effecting the dehydrogenation of amines has been detected in rat brain and liver suspensions by the use of tetrazolium dyes as terminal electron acceptors. Kinetic data on this system are presented and the evidence for requirement of a cofactor is described. Thus, after washing or dialysis, rat brain suspensions have a considerably lowered tetrazolium reducing activity, which can be restored by addition of boiled extracts of rat liver, rat brain, pig liver, or baker's yeast. The heat-stable cofactor in pig liver and rat brain which is necessary for the activity of the tetrazolium reducing system is dialyzable. Pig liver extracts lose their cofactor activity on ashing. The nature of the electron transporting system active in amine dehydrogenation is discussed and the properties of the tetrazolium reducing and the amine oxidase systems are compared.

FURTHER OBSERVATIONS ON THE ENZYMATIC REDUCTION OF TETRAZOLIUM SALTS BY MONOAMINES

1958 ◽  
Vol 36 (6) ◽  
pp. 587-594 ◽  
Author(s):  
J. R. Lagnado ◽  
T. L. Sourkes
Keyword(s):  
Rat Liver ◽  
Metal Binding ◽  
Enzyme System ◽  
Enzymatic Reaction ◽  
Free Base ◽  
Tetrazolium Salts ◽  
Enzymatic Reduction ◽  
Tissue Homogenates ◽  
Cofactor Activity

Studies on the role of purines as cofactors in the enzymatic reduction of tetrazolium salts by monoamines have led to the following results: (1) With whole rat liver extracts as the source of enzymes, several purines exhibit cofactor activity either as the free base or as the corresponding riboside and ribotide derivatives. (2) In contrast to this, mitochondrial material from rat liver is active only if adenylic acid or one of several ribotidic derivatives containing an adenylyl or similar moiety is used as cofactor. (3) Mitochondrial material utilizes hypoxanthine as cofactor for the amine/tetrazolium system only in combination with the supernatant obtained by centrifugation of tissue homogenates at 20,000 g. The additional factor present in this supernatant portion is heat-labile and nondialyzable. The possibility that this additional factor is an enzyme or enzymes converting the free base to the ribotide is discussed.Inhibition studies have revealed that the amine/tetrazolium enzyme system is sensitive to several metal-binding agents, but no direct evidence for the role of a metal in the enzymatic reaction could be obtained. It was also found that nicotinamide and adenine, neither of which exhibits cofactor activity, are potent inhibitors of the enzyme system studied.

FURTHER OBSERVATIONS ON THE ENZYMATIC REDUCTION OF TETRAZOLIUM SALTS BY MONOAMINES

1958 ◽  
Vol 36 (1) ◽  
pp. 587-594 ◽  
Author(s):  
J. R. Lagnado ◽  
T. L. Sourkes
Keyword(s):  
Rat Liver ◽  
Metal Binding ◽  
Enzyme System ◽  
Enzymatic Reaction ◽  
Free Base ◽  
Tetrazolium Salts ◽  
Enzymatic Reduction ◽  
Tissue Homogenates ◽  
Cofactor Activity

Studies on the role of purines as cofactors in the enzymatic reduction of tetrazolium salts by monoamines have led to the following results: (1) With whole rat liver extracts as the source of enzymes, several purines exhibit cofactor activity either as the free base or as the corresponding riboside and ribotide derivatives. (2) In contrast to this, mitochondrial material from rat liver is active only if adenylic acid or one of several ribotidic derivatives containing an adenylyl or similar moiety is used as cofactor. (3) Mitochondrial material utilizes hypoxanthine as cofactor for the amine/tetrazolium system only in combination with the supernatant obtained by centrifugation of tissue homogenates at 20,000 g. The additional factor present in this supernatant portion is heat-labile and nondialyzable. The possibility that this additional factor is an enzyme or enzymes converting the free base to the ribotide is discussed.Inhibition studies have revealed that the amine/tetrazolium enzyme system is sensitive to several metal-binding agents, but no direct evidence for the role of a metal in the enzymatic reaction could be obtained. It was also found that nicotinamide and adenine, neither of which exhibits cofactor activity, are potent inhibitors of the enzyme system studied.

scholarly journals Enzymic synthesis of ether types of choline and ethanolamine phosphoglycerides by microsomal fractions from rat brain and liver

1977 ◽  
Vol 18 (1) ◽  
pp. 53-58
Author(s):  
A Radominska-Pyrek ◽  
J Strosznajder ◽  
Z Dabrowiecki ◽  
G Goracci ◽  
T Chojnacki ◽  
...  
Keyword(s):  
Rat Brain ◽  
Enzymic Synthesis ◽  
Ethanolamine Phosphoglycerides ◽  
Rat Brain And Liver

Respiration of Rat Brain and Liver at Temperatures above 37°C

1951 ◽  
Vol 24 (2) ◽  
pp. 163-166
Author(s):  
Robert L. Jasper ◽  
James W. Archdeacon
Keyword(s):  
Rat Brain ◽  
Rat Brain And Liver

The Effect of Aluminum on Rat Brain and Liver Quinolinic Acid Concentrations

1991 ◽  
pp. 459-462
Author(s):  
J. H. Connick ◽  
G. Lombardi ◽  
F. Moroni ◽  
E. Hall ◽  
A. Taylor ◽  
...  
Keyword(s):  
Rat Brain ◽  
Quinolinic Acid ◽  
Rat Brain And Liver

Different Regiospecificity in the Hydroxylation of the Antidepressant Desmethylimipramine Between Rat Brain and Liver

1992 ◽  
Vol 71 (6) ◽  
pp. 416-419 ◽  
Author(s):  
T. Hansson ◽  
C. Bahr ◽  
M. Marklund ◽  
J.-O. Svensson ◽  
M. Ingelman-Sundberg ◽  
...  
Keyword(s):  
Rat Brain ◽  
Rat Brain And Liver
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