Figure 4.

Fittings of partial oxygen pressure (pO₂) depth profiles and calculation of oxygen consumption. Fittings (black lines) of representative pO₂ depth profiles during the three different activity states of the hippocampal CA3 network, i.e., tetrodotoxin (TTX) (A), spontaneous network activity (SPON) (B), and gamma oscillations (GAM) (C) as obtained from experiments illustrated in Figure 3. Note that pO₂ depth profiles show a convex behavior. The data were fitted from the upper slice surface to the lowest pO₂ value. (D) Quantification of oxygen consumption in the absence of spiking (TTX, n=8), during spontaneous network activity (SPON, n=19), and during gamma oscillations (GAM, n=8), given in arbitrary units (a.u.). Note that oxygen consumption during gamma oscillations was 2.2-fold and 5.3-fold higher as compared with spontaneous network activity and absence of spiking. Statistical significance is marked by asterisks (P<0.05).