[Cardiotropic activity of synthetic peptide CH3CO-Lys-Lys-Arg-Arg-NH2 (protectin)].

Peptide CH3CO-Lys-Lys-Arg-Arg-NH2 (protectin) was synthesized and its activity was studied on the model of experimental myocardial infarction in rats in comparison to the reference antihypoxant drug riboxin. Intranasal injections ofprotectin at doses within 2-20 microg/kg once a day by course of 7 days produced a pronounced anti-ischemic action, improved coronary circulation of the blood, increases contractile activity of myocardium, reduced intensity of lipid peroxidation, and improved antioxidant protection. In some respects (improved coronary circulation of the blood, increased antioxidant protection), protectin was more effective than riboxin.

[Heart rate in Daphnia magna as a functional test for assessing efficacy of chemical agents].

It is suggested to use Daphnia magna Straus as a biotest object for the evaluation of heart rate (HR) as a functional parameter. The influence of cholinergic ligands (atropine and carbamylcholine) on the Daphnia cardiac rhythm has been studied. It is found that the cholinergic agonist and antagonist produced opposite influence on the HR and are capable of prevent the action of each other.

[Detection of a cross-reacting antigen common to multilaminar epithelia and group A streptococcus in cells of human epidermal tumors].

The tissue-specific antigen of basal cells of human squamous epithelium which cross-reacts with streptococcal group A antigen has been detected in the cytoplasm of cells of human basal cell and squamous cells carcinomas histogenetically related to the skin epithelium. The antigen has not been detected in cells of tumors of endodermal origin (gastric and intestinal adenocarcinomas). These findings together with previous reports on the existence of cross-reactivity in case of animal tumors of ectodermal genesis may form the basis for an additional method of differential diagnosis of human tumors arising from the ectoderm-derived epithelium.