inhibition of human erythrocyte glucose 6-phosphate dehydrogenase activity by dehydroepiandrosterone and related steroids.

INHIBITION OF HUMAN ERYTHROCYTE GLUCOSE 6-PHOSPHATE DEHYDROGENASE ACTIVITY BY DEHYDROEPIANDROSTERONE AND RELATED STEROIDS.

The inhibitory effects of several steroids on G6PD activity using intact erythrocytes are reported. Incubation of whole blood with dehydroepiandrosterone (DHEA) resulted in 42% and 12% inhibition in the enzyme activity in the presence and absence of oxygen, respectively. Addition of epinephrine and/or aminophylline into the incubation medium caused further enzyme inhibition suggesting a po...

Inhibition of Human Erythrocyte Glucose 6-Phosphate Dehydrogenase by Cadmium, Nickel and Aluminium

inhibition of human erythrocyte glucose 6-phosphate dehydrogenase by cadmium, nickel and aluminium

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Inhibition of Mammalian Glucose-6-phosphate Dehydrogenase by Steroids.

It has been considered for some time that steroid hormones may exert their regulatory effects by influencing certain enzymes.' However, our present knowledge of the mechanisms of steroid action upon enzymes is limited. Estrogens have been shown to stimulate the transfer of hydrogen between diand triphosphopyridine nucleotides,2 ' although there is disagreement as to the role of steroids in this...

Inhibition of Human Erythrocyte Glucose 6-Phosphate Dehydrogenase by Cadmium, Nickel and Aluminium

The inhibition of human erythrocyte glucose 6-phosphate dehydrogenase (G6PD) by Cd (II), Al (III) and Ni (II) was studied. The enzyme was partially purified having specific activity of 1.4 U/mg protein. Cadmium inhibited G6PD activity progressively up to 1.5 mM concentration where about 65% of the enzyme activity was lost. The inhibition was uncompetitive and noncompetitive with respect to gluc...

Genetic Variants of Human Erythrocyte Glucose-6-phosphate Dehydrogenase

The values of V,,,,, and K, for the three genetic variants A, B, and Aof erythrocyte glucose-&phosphate dehydrogenase have been determined at 10 different pH values in the range from 5.5 to 9.5, and at four different temperatures in the range from 18.5-40.0”. The log V,,,,, versus pH curve for each of the enzymes shows a monotonic increase between pH 5.5 and 7, and a plateau from pH 7.5 upwards...