Figure 9. Mechanism of action of propofol induced anesthesia.
(A) Model of propofol anesthesia implementing inhibition of ACh and HA release and increase in the decay time constant of the GABAergic IPSPs. From top to bottom: Spatio-temporal pattern of activity in PY neurons, average activity in PY network (simulated LFP), band-filtered (7–15 Hz) PY LFP. The GABA decay time constant was increased by 150%; ACh and HA were reduced to the same level as in simulations of the natural sleep in cats. Note significant amount of spindle activity. (B) The model where only the GABA time constant was increased by 150%. Note an almost complete absence of spindle activity. (C) Network activity during simulated natural SWS in cat model. Note decreased spindle activity compared to the propofol simulations in panel A. (D) Power in 0.2–4 Hz and 8–15 Hz bands for all three conditions. The network was divided into 10 groups of 50 neurons. Membrane voltages were averaged within each group, then FFT was used to estimate power in each group. Bar height indicates average across 10 groups, error bar indicates standard deviation across 10 groups.