Figure 9.

Diagram summarizing findings of this study. Top: in regularly cycling females (control), somatosensory stimulation leads to the release of a stimulus-evoked vasodilation onto parenchymal arteriole smooth muscle cells (SMCs), which leads to activation of large-conductance Ca²⁺-activated K⁺ channels (BK_Ca), K⁺ efflux, arteriolar dilation, and functional hyperemia. Bottom: after menopause (Meno), BK_Ca function in arteriolar SMC is impaired, associated with an increase in spontaneous myogenic tone and lower resting lumen diameter. In addition, functional hyperemia is blunted, leading to a smaller increase in perfusion after whisker stimulation.