fig2

Figure 2. Ion channel signalling in the microvasculature. Regulation of SMC contractility is dependent upon calcium signalling. Microvascular SMC express multiple ion channel subtypes that can influence the level of Ca²⁺ within the cell, and there is a complex interplay and balance between the channel sub-types. The balance of this signalling dictates whether the cell undergoes contraction/relaxation, proliferation or migration. Black arrow: stimulatory. Red arrow: inhibitory. Dashed arrow: indirect. K_Ca: Calcium-activated potassium channel; Ca_V: voltage-gated calcium channel; IP₃: inositol triphosphate; IP₃R: inositol triphosphate receptor; K_ATP: ATP-activated potassium channel; K_IR: inwardly-rectifying potassium channel; K_V: voltage-gated potassium channel; NO: nitric oxide; PKA: protein kinase A; PKC: protein kinase C; RyR: ryanodine receptor; TRPC: transient receptor potential C; TRPM: transient receptor potential M.