Changes of heart rate variability at the stimulation and blockade of central serotoninergic structures in rats

Simulation of central serotoninergic system (SCSS) (5-hydroxy-L-tryptophan, 50 mg / kg b.w. in a combination with fluoxetine, 3 mg / kg b.w.) sharply reduces of all waves capacities of heart rate variability (HRV) and increases heart frequency at rats. The reaction on SCSS can be maximal or moderate, but in both variants carries expressed sympathomimetic character. Blockade of central serotoninergic system (BCSS) (ketanserine and granisetron, on 0,1 mg / kg b.w.) at 60 % animals also oppresses the waves of spectrum HRV, but in a smaller measure, than SCSS. BCSS causes short increase of capacity HF and VLF-waves in 40 % of rats. It is supposed, that central serotoninergic structures participate in modulation of waves of HRV, is especial HF, mainly in a direction of their decrease.