INVOLVEMENT OF LATERAL SEPTUM INTO THE CENTAL NERVOUS SYSTEM REACTION ON ACUTE ALCOHOL INTOXICATION

Abstract

The objective of this study - to determine how lateral septum (LS) is involved into thebrain reaction on acute alcohol intoxication (AAI) based on the changes in its electricalactivity and reaction of local nitrergic system.Material and methods. Wistar rats (n=8 for electrophysiology and n=6 for histochemistryof nitrergic system) were used for the study. Changes in the spectral power of the localfield potential, neural noise dynamics, as well as changes in the number of NOS-positivecells in LS for the model of AAI by intraperitoneal injections of ethanol solution (2 g/kg)were studied.Results. An increase in power for delta, theta, beta-2, gamma frequency bands, andultrafast oscillations as well as suppression of beta-1 rhythms was observed as aresponse of LS to AAI. Furthermore, we have detected an increase in neural noise forall frequency range. Inspection of specific frequency bands showed a decrease in neuralnoise for delta, theta, and beta bands as compared with spontaneous levels. In additionto that, ethanol-induced reduction in neural noise was measured for gamma frequencyrange and ultrafast oscillations. AAI resulted in activation of a population of medium/small-sized LS neurons the number of which increased from 3.15 ± 0.31 cells per sliceto 7.06±0.67 cells per slice (P = 0.0122).Conclusion. Our findings on the ethanol-induced changes in oscillatory activity andneural noise dynamics in LS coupled with activation of the nitrergic system allowed us toincorporate LS in the neural circuit engaged in the brain reaction to AAI.