Abstract
The effect of insulin and cortisol on glucose metabolism of thymus lymphocytes from
adrenalectomized rats was studied. The addition of 10-8 M insulin increased glucose uptake, lactate production and the production of 14CO2 from labeled glucose at an initial concentration of 1.1 mM. Insulin stimulation of
glucose metabolism was antagonized by 10-6 M Cortisol, which inhibited glucose metabolism with or without insulin present.
At a glucose substrate concentration of 11 mM, it was not technically possible to
measure glucose uptake, but the presence of 10-8 M insulin increased lactate production 32% and caused a small but statistically significant
increase in glycogen content. As with the lower substrate concentration, 10-8 M cortisol opposed the effects of insulin by decreasing both lactate production and
glycogen content of the cells. It may be concluded that thymus lymphocytes can display
insulin sensitivity under physiologic conditions.
Key words
Insulin - Cortisol - Glucose Metabolism - Thymus Lymphocytes - Glycogen
1 This work was supported by US Public Health Service Research Grant CA10291 from the
National Cancer Institute. The studies reported were taken from a thesis submitted
to the Univ. of Nebraska in partial fulfillment of the requirements for the Ph.D.
degree.
2 Present address: Department of Biochemistry, University of Oregon Medical School,
Portland, Oregon, USA.
