Figure 3.

Cellular [Ca²⁺]_i responses of a pressurised mesenteric artery during tonic constrictions. (a) Confocal images of [Ca²⁺]_i levels in individual smooth muscle cells of a pressurised artery at rest and immediately following agonist stimulation. (b) Consecutive confocal images showing the [Ca²⁺]_i response during continued stimulation with PE (10 μM), images are separated by 1.02 s. Several cells can be seen responding out of phase with each other. (c) Traces from one cell responding to PE (10 μM) or U46619 (10 μM). The cell from which measurements were taken is marked by the white circle in the second image of panel A. (d) Montage of six consecutive frames (1 s apart) in one smooth muscle cell of an intact artery exposed to 10 μM PE. A wave is initiated in a confined region of the cell and then spreads throughout the length of the cell. (e) Continuous line plots of [Ca²⁺]_i changes in 13 individual smooth muscle cells of a pressurised artery on exposure to PE (10 μM); the [Ca²⁺]_i changes appear asynchronous. The averaged signal from all 13 cells is indicated by the thicker black line.