Figure 5. A role for NO in vasodilatation induced by muscle contraction at 60 cpm can be observed only after K⁺ release channels are inhibited.

A, the change in diameter in response to muscle contraction under the capillaries at 6 cpm in the absence (□) and presence (■) of l‐NAME (nitric oxide synthase activity inhibitor). ^*Vasodilatation induced by muscle contraction alone differed significantly from muscle contraction in the presence of l‐NAME. B, the change in diameter in response to muscle contraction under the capillaries at 6 cpm in the absence (□) and presence of DAP (voltage dependent K⁺ channel inhibitor) (▲) and DAP+l‐NAME (●). ^*Vasodilatation induced by muscle contraction alone differed significantly from muscle contraction in the presence of DAP+l‐NAME. C, the change in diameter in response to muscle contraction under the capillaries at 60 cpm in the absence (□) and presence (■) of l‐NAME. D, the change in diameter in response to muscle contraction under the capillaries at 60 cpm in the absence (□) and presence of DAP (▲) and DAP+l‐NAME (●). ^*Vasodilatation induced by muscle contraction alone differed significantly from muscle contraction in the presence of DAP+l‐NAME. Protocol details can be found under Protocol 3 and raw baseline and maximal diameters can be found in Table 3.