The significance of potassium and sodium for the synthesis of glycogen in the isolated rat diaphragm

Abstract

The synthesis of glycogen was studied at various concentrations of potassium in the diaphragm. It was found that glycogen synthesis is increased when potassium is lost from the tissue. During incubation in normal Krebs-Ringer-bicarbonate, 6.7 mequiv. K/100 g dry weight are lost and 100 mg of glycogen/100 g wet weight are synthesized. Removal of potassium ions from the medium leads to a loss of 11.6 mequiv. K from the tissue, and 173 mg of glycogen are synthesized. An increase of potassium ions in the medium to 17.6 mequiv./l lowers the potassium loss from the tissue, but is without effect on the synthesis of glycogen. The role played by sodium in glycogen synthesis is discussed, together with questions connected with the synthesis of glycogen and the entrance of potassium into the cell.