The effect of glucose, insulin and dexamethasone upon 7-ethoxycoumarin O-deethylase activity of adult rat hepatocytes in primary culture.

The influence of glucose, insulin and/or dexamethasone on the 7-ethoxycoumarin O-deethylase activity of rat hepatocytes in primary culture was investigated. The addition of extra glucose to the medium attenuated the fall in enzyme activity observed during the first 24 h in culture, this effect being dose-dependent. The inclusion of insulin further enhanced this effect, but glucose + insulin did not prevent the decrease in enzyme activity in the subsequent 48 h. The inclusion of dexamethasone, alone or in combination with glucose + insulin, also attentuated the initial decline in enzyme activity. After 24 h in culture, the enzyme activity increased such that after 72 h in culture, the activity was greater than that measured in the freshly isolated cells.