RESUMO
Rats were immunized with bovine serum albumin conjugated with 5-hydroxytriptamine (5-HT). Two injections with a 2-week interval were carried out. At first, rats were injected subcutaneously (2 mg/kg, 0.25 ml) with Freund's adjuvant complete. The second injections (10 mg/kg intraperitoneally) was made 2 weeks later without the adjuvant. One week after the first antigen injection, there were a decrease in the relative power of the electrical activity of the caudate putamen, neocortex, and amygdala in the delta 2 and theta 2 bands and its increase in the alpha and beta-ranges. The number and duration (total and mean) of REM sleep episodes as well as REM sleep contribution in the total sleep duration decreased. These findings testify to a reduced functional activity of the central serotonergic system. Four-five weeks after the first injection, a tendency to a recovery of the bio-electrical spectral pattern and diurnal sleep structure was revealed. Five weeks after the first antigen injection, the titre of antibodies to 5-HT was 1:32-1:64.