[Relationship between membrane conformation changes and several metabolic processes in antigen-stimulated...

The changes are followed up in the properties of the macrophage membrane after treatment with phospholipase C and the activity of the glucose-6-phosphate dehydrogenase enzyme in order to elucidate the link between the conformation changes observed and some metabolic prosesses in antigen-stimulated macrophages. The studies were carried out on peritoneal macrophages of guinea pig-treated in vitro with phospholipase C. It was found that: 1. The action of phospholipase C essentially changes the linking parameters available for the fluorochrome 1-aniline-8-naphthalin sulfonic acid. 2. The activity of the glucose-6-phosphate dehydrogenase rises by 34.5% in the phospholipase C-treated macrophages. The fast changes observed in the conformation of the membrane that was studied under the effect of the fluorescence stain AHC, the higher activity of the dehydrogenase enzyme used after phospholipase C treatment, the fact that phospholipase C failed to pass through the macrophage membrane, and the capacity of the latter enzyme to bring about the same metabolic changes in the stimulation of the hexosomonophosphate cycle of the normal macrophages as well as the antigen stimulation produced made it reasonable to believe that the conformation changes produced a 'signal' that is transmitted through the cell membrane, and hence the metabolic changes that followed in the metabolic processes.