Reversible inhibition of the hydrocortisone induction of glycerol phosphate dehydrogenase by cytochalasin B in rat glial C6 cells. [Model for mechanisms of action of steroids]

Technical Report · Thu Jan 01 04:00:00 EST 1976

OSTI ID:7336247

Bennett, K; de Vellis, J

The hydrocortisone (HC) induction of glycerol phosphate dehydrogenase in rat glial C6 cells was inhibited reversibly and in a dose-dependent manner by cytochalasin B (CB). Addition of sodium pyruvate to the culture medium did not reverse the inhibitory effect of CB, suggesting that CB did not act by blocking glucose transport. CB had no effect on basal level GPDH, and total cellular RNA, DNA or protein content. Colcemid had no effect on the induction, suggesting that the integrity of microtubules is not necessary for the induction process. CB did not alter the rate of degradation of induced GPDH nor did it act as an inhibitor of general protein synthesis. CB appears to specifically inhibit GPDH synthesis whether it was given before, simultaneously or after the addition of HC to the cultures. This effect of CB is correlated with a marked decrease, up to 60 percent, in specific nuclear binding of (/sup 3/H)-HC added to the culture media, even though total cell uptake of (/sup 3/H)-HC was unaffected. According to the current model of HC action, the nuclear effect of CB would result in reduced synthesis of mRNA for GPDH. Since CB dissociated microfilaments in C6 cells, we hypothesize that microfilaments may play a role in the hormonal induction process.

• Research Organization: California Univ., Los Angeles (USA). Lab. of Nuclear Medicine and Radiation Biology
• OSTI ID: 7336247
• Report Number(s): UCLA-12-1101
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
ADRENAL HORMONES
ANIMAL CELLS
ANIMALS
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL EFFECTS
BIOLOGICAL MODELS
CORTICOSTEROIDS
ENZYMES
GLUCOCORTICOIDS
HORMONES
HYDROCORTISONE
HYDROGENASE
HYDROXY COMPOUNDS
IN VITRO
KETONES
KINETICS
MAMMALS
ORGANIC COMPOUNDS
OXIDOREDUCTASES
PREGNANES
RATS
REACTION KINETICS
RODENTS
STEROID HORMONES
STEROIDS
VERTEBRATES