[Endothelial relaxation factor as a local modulator of arterial function. The possibility of stabilization].

Endothelium-derived relaxing factor (EDRF) exerted no inhibitory effect on papillary muscles or the rat portal vein. Externally applied acetylcholine did not reach aorta endothelium to stimulate the EDRF release in rabbits, nor bradykinin in the pig coronary artery segments. Acetylcholine penetrated, however, canine femoral artery wall and stimulated the release of EDRF.

[The role of rhythmic structures of the aortic intima in the development of atherosclerosis].

A study was made of 606 specimens from dead males aged 20 to 39. The frequency and area of rhythmical structures (RS) of lipid spots and fibrous patches of aorta were determined after staining of aortae with Sudan IV. RSs were revealed in persons aged 20-29 and 30-39 in 70%.

[Increase of the water content in the lipid phase of lipoproteins during peroxidation].

By means of fluorescent probes of pyrene and 4-dimethylaminochalcone (DMC) an increase of polarity of the lipid phase of lipoproteins of low density LDL during their autooxidation was discovered. The observed change of polarity is explained by the penetration of water molecules into the LDL phospholipid layer, which form hydrogen bonds with polar groups resulting from the peroxidation of lipids. Such "water corrosion" of the membranes is suggested to bring about a change of matrix properties of the phospholipid layer, particularly a change in LDL protein conformation discovered earlier during peroxidation.

[Lipoxygenases of animals: changes in lipoxygenase activity from reticulocytes during interaction with blood plasma lipoproteins].

A homogeneous sample of lipoxygenase from rabbit reticulocyte cytosol was obtained. The rate of exogenous arachidonate oxidation by reticulocyte lipoxygenase was found to increase in the presence of various blood plasma lipoproteins of mammals. The rate of arachidonate oxidation by soybean lipoxygenase in the presence of these lipoproteins was either unaffected or decreased.