[Structural effects in the sarcolemma of the cardiomyocytes under the action of modulators of the polyphosphoinositide system].

The influence of activators (Ca(2+)-channels stimulator BAY K 8644 and phospholipase C stimulator fMLP) and inhibitors (Ca(2+)-channels blocker verapamil and alpha 1-adrenoceptors blocker prazosin) of the polyphosphoinositide system on cardiomyocytes sarcolemma, was studied. The structural effects of the PPI modifiers seem to be one of the mechanisms of the PPI physiological activity at the membrane level.

[Structural effects in membranes after exposure to methyl (embiquin) and metaxylyl derivatives of chloroalkylamines].

Chloroaklylamine derivatives are studied for their effect on the structural organization of mitochondrion and microsome membranes of the cattle liver. The antitumoural preparation--embiquin is shown to increase microviscosity of hydrophobic zones of a lipid matrix of mitochondrial membranes and to decrease the quantity of immobilized cytochrome C, whereas it has no effect on microsomal membranes. It is established that the replacement of a methyl substituent in the nitrogen atom of chloroalkylamines by the metaxylyl one evokes no qualitative differences in the character of disturbances of the structural properties of mitochondrial membranes, however it induces structural perturbations in the microsomal membranes.

[Changes in the secondary and tertiary structure of serum albumin in interactions with ligands of various structures].

High affinity interactions between blood serum albumin and five substances of various chemical structure, exhibiting distinct physiological activity, were accompanied by alterations in the protein tertiary structure, while the albumin secondary structure was involved in conformational transformation after less effective affinity binding.