[Stress-protective activity of the CH3CO-Lys-Lys-Arg-Arg-NH2 synthetic peptide (protektin)]

The CH3CO-Lys-Lys-Arg-Arg-NH2 peptide (the author has named it protectin) was synthesized, and its activity was studied during different stress actions. Protectin was found to normalize the content of corticosterone and adrenalin in adrenal glands and blood after its intranasal administration to rats one day before a cold or heat shock, or hypobaric hypoxia at doses of 1-10 microg/animal and after its intravenous administration just after acute hemorrhage at doses of 0.5-2 microg/animal. The intranasal administration of protectin at doses of 1-10 microg/rat one day before the heat or cold shock was also shown to prevent a change in the content of free histamine and the activity of diamine oxidase in myocardium, which was induced by the dramatic change in the activity of the enzyme after the temperature actions.