[The relationship between the formation of trace reactions and the functional state of rats of different genetic lines].

The level of excitability of the nervous system was enhanced in rats of the Krushinsky--Molodkina (K--M) and Wistar (W) lines by means of dynamic and static physical loads and injections of different doses of al-amphetamine. It was shown that a higher level of excitability of the central nervous system produced in both lines of rats improved memory and increased the rate of formation of a conditioned active aboidance reflex (CAAR). A greater physical load or dose of the stimulant drug in the K-M line of rats resulted in a decrease of all parameters characterizing CAAR, while in the other line they rose in progression. The data obtained are believed to be related to a different genetically conditioned initial level of excitability in the indicated lines of rats--a higher one in the K--M line animals as compared with the W line rats, which determines a different norm of the nervous system responsiveness in the indicated groups of animals.