[Prevention of arrhythmia in acute ischemia in conscious animals using a serotonin analog]. / Preduprezhdenie aritmii pri ostroi ishemii u bodrstvuiushchikh zhivotnykh s pomoshch'iu analoga serotonina.

The state of the serotonergic system was studied in adaptation of rats to short-term non-damaging stress actions along with the possibility of protecting the heart of conscious animals against arrhythmias in acute ischemia with the serotonin analogue 4-nitro-5-methoxytryptamine. It was shown that the adaptation resulted in a significant increase in rat midbrain serotonin by 70%. Preliminary administration of the serotonin analogue 3 fold reduced the total duration of arrhythmias and approximately 5 fold--the heart fibrillation rate and the death rate of animals in acute ischemia. The data obtained are in agreement with the idea on the role of stress-limiting systems in prevention of stress-induced and ischemic damages of the organism. They show that protective effects of metabolites of these systems can be successfully reproduced with their synthetic analogues or activators.

[Radioprotective effectiveness and toxicity of 4,5-disubstituted tryptamines]. / Radiozashchitnaia éffektivnost' i toksichnost' 4,5-dizameshchennykh triptaminov.

In experiments on mice a study was made of different substituents in the 4th position of the indole ring of 5-methoxytryptamines (5-MOT) on toxicity and radioprotective efficiency of the compounds of this class. It was shown that the administration of the amino-group to a mexamine molecule increased the preparation toxicity; the nitro-group somewhat diminished the toxic properties, and the acetylamino group did not change 5-MOT toxicity. A 5-MOT derivative with a nitro group possessed the strongest radioprotective action. The radioprotective efficiency of these compounds persisted for 1-2 h.