ACTIVITIES OF GLYCOGEN-PHOSPHORYLASE AND GLYCOGEN-SYNTHETASE IN EEL NEUTROPHILS

The existence of glycogen phosphorylase and glycogen synthetase was histochemically demonstrated in the neutrophils of eel (Anguilla japonica) under inflammatory condition by the reaction of polysaccharide derived from glucose-1-phosphate or uridine diphosphate glucose with iodine and PAS, respectively. The enzyme activities were also determined in the peripheral and pronephros neutrophils obtained from the fish after an intraperitoneal injection of formalin-killed Edwardsiella tarda or physiological saline. The activity of the glycogen phosphorylase was measured by the amount of the released inorganic phosphate from glucose-1-phosphate, and that of the glycogen synthetase by the amount of the released uridine diphosphate from uridine diphosphate glucose. In the pronephros neutrophils from the fish injected with fromalin-killed E. tarda, the reaction of glycogen phosphorylase became prominent between 24 and 48 hours after injection, while that of glycogen synthetase increased conspicuously from 3 hours. But there were no significant differences in the reactions of two enzymes between the control fish injected with physiological saline and normal fish. The activities of glycogen phosphorylase and glycogen synthetase in the peripheral neutrophils did not differ between the bacteria-injected and control fish, but those, especially D-form of glycogen synthetase, in the pronephros neutrophils were greatly increased in the bacteria-injected fish. From the results of histochemical reactions and enzyme activities of these two enzymes, it is suggested that the increase in glycogen contents of neutrophils under inflammatory condition resulted from the activation of D-form of glycogen synthetase which had been achieved in the pronephron before being emigrated into the peripheral blood.