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Biomedical subjects

K Kakinuma

Publications and source records attributed to K Kakinuma.

At least 127 records · Page 7Linked to original sources

Effect of ionic sites of surfactants on leukocyte metabolism.

The effect of ionic and nonionic surfactants on the metabolism of leukocytes was studied. Among anionic surfactants, sodium laurylsulfate, sodium laurate, and sodium lauroyllactate stimulated oxygen uptake and glucose oxidation through the hexose monophosphate pathway. The magnitude of the effect of anionic surfactants seemed to be related to the electrostatic strength of the ionic site of each compound. Cationic, amphoteric, and nonionic surfactants were inhibitory to leukocyte metabolism.

Animals↗

Studies on the mechanism of metabolic stimulation in polymorphonuclear leucocytes during phagocytosis. I. Evidence for superoxide anion involvement in the oxidation of NADPH2.

1. The oxidation of NADPH2 by leucocyte granules, as measured at acid pH in the presence of Mn-2+, was found to be inhibited by superoxide dismutase. 2. Omission of Mn-2+ markedly lowered the oxidase activity at acid pH, which was still inhibited by superoxide dismutase. 3. At alkaline pH the oxidase activity was lower than at acid pH. 4. During oxidation of NADPH2 by leucocyte granules, reduction of cytochrome c occurred which was partially inhibited by superoxide dismutase. 5. It was concluded that NADPH2 oxidation occurs through an enzymatic reaction and a nonenzymatic chain reaction. Superoxide anion (O-minus-2 and NADPH- free radical would be involved in the chain reaction. The differential sensitivity of NADPH2 oxidation to superoxide dismutase in different experimental conditions (see above 1, 2 and 3) was explained on the basis of changes in the properties of the chain reaction.

Animals↗

Studies on the mechanism of metabolic stimulation in polymorphonuclear leucocytes during phagocytosis. II. Presence of the NADPH2 oxidizing activity in a myeloperoxidase-deficient subject.

1. The biochemical properties of leucocytes from a myeloperoxidase-deficient subject were compared with those of leucocytes from healthy subjects. 2. Myleoperoxidase-deficient leucocytes responded to phagocytosis of heat-killed bacteria with increased respiration, increased oxidation of glucose through the hexose monophosphate shunt and increased production of H2O2 as normal leucocytes do. 3. The ability of granules isolated from myeloperoxidase-deficient leucocytes to oxidize nicotinamide coenzymes was comparable to that of granules isolated from normal leucocytes. 4. The results argue against the hypothesis that oxidation of NADPH2 in leucocytes is performed by myeloperoxidase.

Adult↗