Sven Lindvall

Influence of various compounds on the degradation of hyaluronic acid by a myeloperoxidase system.

Myeloperoxidase in the presence of 0.7 mM hydrogen peroxide degrades hyaluronic by a mechanism which involves iron. Degradation is enhanced in the presence of chloride ion, which is attributed to the formation of hypochlorous acid. Myeloperoxidase-dependent degradation of hyaluronic acid is inhibited by superoxide dismutase, desferrioxamine, iodide ion, bromide ion, mannitol, histidine and various antiinflammatory agents. The destructing agent is presumably the hydroxyl radical.

MECHANISM OF ABSORPTION OF TWO INTRAMUSCULAR IRON PREPARATIONS

The mechanism of absorption from an intramuscular depot of an iron‐sorbitol‐citrate and an iron‐dextran complex has been studied in anaesthetised cats in which the lymph vessels were cannulated. The results are discussed in relation to the molecular size of the two iron complexes

Studies on a new cellulase preparation from Penicillium. I. Method of determining enzymatic activity.

The viscosimetric method described is suitable for the determination of enzymatic activity when the substrate is a polyelectrolyte or a polymer to which Staudingers law is not applicable. It has been tested experimentally for determining the activity of cellulase isolated from Penicillium, with carboxymethylcellulose as substrate.

Influence of thiols on the chlorinating effect of a myeloperoxidase system

The structure-activity relationships for the interactions of a number of sulfhydryl compounds on the transformation of (Z)-3-(4-bromophenyl)-3-(3-pyridyl)allylamine (CPP 200) by an MPO-H2O2-Cl-(-)system at pH 5.25 have been studied. It was found that the inhibitory effect of the thiol group was strongly dependent on the presence of an electron-withdrawing NH3(+)-group in the molecule. Also, the acid-base properties of the thiolic compounds were involved in the inhibitory mechanisms.

(Z)-3-(4-Bromophenyl)-3-(3-pyridyl)allylamine as substrate for studies of myeloperoxidase activity

(Z)-3-(4-Bromophenyl)-3-(3-pyridyl)allylamine (CPP 200) is transformed to the corresponding chloroimine by hypochlorite ion (ClO-) formed in the presence of myeloperoxidase. A scheme for this transformation is given. The influence of various compounds on this process has been studied. Cysteamine, cysteine and 6-chloro-3-hydrazino-pyridazine inhibited the transformation of CPP 200, while some p-hydroxyphenyl derivatives increased the rate of transformation of CPP 200. The increase seen on addition of the p-hydroxyphenyl derivatives is not a chloride-dependent reaction. Various mechanisms for the inhibiting effect as well as for the activating effect on the transformation of CPP 200 are discussed.