Inactivation of glycogen phosphorylase of human polymorphonuclear leukocytes

Glycogen phosphorylase of human polymorphonuclear leukocytes is dephosphorylated during incubation of a gel-filtered cell extract. The dephosphorylated enzyme (b form) retains 25 per cent of the activity of the phosphoenzyme (a form) when measured without AMP but a high glucose-1-phosphate concentrations. The ratio of activity -AMP/+AMP for the a enzyme is 0.8-1.0 and for the b enzyme 0.2. Leukocyte phosphorylase is not activated by -SH groups, but the b enzyme is stimulated by 0.4 mol/1 Na2SO4. The phosphatase which catalyzes the conversion of phosphorylase a to b is inhibited by glucose-1-phosphate and AMP both a 14 degrees C and 25 degrees C. Glucose counteracts the AMP inhibition but not the glucose-1-phosphate inhibition at both temperatures. Glucose alone had no effect at 25 degrees C, but it accelerated the phosphatase reaction at 14 degrees C. Glucose-6-phosphate or glycogen alone or in the presence of AMP or glucose-1-phosphate did not affect the phosphatase reaction. From previous and present experiments it is concluded that the phosphorylase of human polymorphonuclear leukocytes is closely related to liver phosphorylase and that the inactivation of the enzyme is mainly controlled by AMP and glucose.

Amylo-1,60glucosidase deficiency (glycogenosis type III) in the Faroe Islands

Seven cases of glycogenosis type III (amylo-1,6-glucosidase deficiency) in two probably related families from the Faroe Islands are presented. The group of patients comprised two pairs of sibs. In a total of 78 members of the two families case histories were obtained and clinical examinations, analyses of amylo-1,6-glycosidase activity in erythrocytes and leucocytes, determinations of red cell, serum and enzyme groups as well as HL-A types were performed. In addition, all patients were subjected to studies of liver function. The distribution patients in these families supports the assumption of autosomal recessive inheritance. Heterozygotes could not be diagnosed with certainty by the methods of enzyme activity analysis employed. The incidence of glycogenosis type III with amylo-1,6-glucosidase deficiency was found to be high in the Faroe Islands.

Effect of methylprednisolone on some BCG-mediated changes in rabbit alveolar macrophage

The effect of methylprednisolone sodium succinate treatment on Bacillus Calmette-Guérin (BCG) immunization was examined in alveolar macrophages of New Zealand White rabbits. Intravenous BCG injection caused a marked increase in cell number and in the hexosemonophosphate shunt activity. There was also a selective augmentation in the activity of acid phosphatase and beta-glucuronidase and an increase in lysosomal density. Activity of the lysosomal phospholipases was decreased. Steroid treatment suppressed the BCG-induced increase in cell number, hexosemonophosphate shunt activity, acid phosphatase, and beta-glucuronidase, and prevented the increase in lysosomal density. On the other hand, steroid treatment increased the activity of the phospholipases to levels higher than either control values or those obtained with cells from BCG-treated rabbits.