Figure 4.

Group-averaged blood-oxygenation-level-dependent (BOLD) (left), relative cerebral blood flow (rCBF) (middle) and cerebral arterial blood volume (ΔCBV_a) (right) responses of the sensory (upper) and the hippocampus area (lower) to CO₂ stimulation. The dynamics of BOLD and ΔCBF were similar, but their peak response was much higher for spontaneously hypertensive rats (SHR). The ΔCBV_a responses in SHR appeared to have a slightly shorter time-to-peak and faster return with similar amplitude of signal changes. Error bars: s.e.m.. WKY, Wistar–Kyoto rats.