Separation of effects of adenosine on energy metabolism from those on cyclic AMP in rat thymic lymphocytes.

In rat thymic lymphocytes incubated for 2 h without exogenous energy-providing substrate, adenosine may be substituted for glucose as a means of maximally restoring energy metabolism and those cellular functions whose rates are sensitive to small changes in the energy balance, such as protein synthesis and uridine utilization for RNA synthesis (Nordeen, S. K., and Young, D. A. (197615.Biol.Chem.251, '7295-7303).Since effects of adenosine in thymocytes and other cells have frequently been attributed to changes in cyclic AMP, this report investigates its possible involvement in these glucose-like restorative actions of adenosine.Although the same range of doses of adenosine effective at raising cyclic AMP also elicit roughly parallel stimulations of protein synthesis and uridine utilization, further results dissociate the restorative actions from