Figure 3.

Experimental dependence of calcium wave propagation direction on intrinsic islet heterogeneity and applied heterogeneity. (A) Proportion of calcium waves that propagate with respect to an applied glucose gradient originating from the side at elevated glucose (high to low) or the side at low glucose (low to high), or in an unrelated direction (indeterminate). (B) Proportion of calcium waves under a glucose gradient that propagate with respect to the preferred wave direction at uniform glucose levels, where the gradient is applied toward or against the preferred direction. (C) Proportion of calcium waves under uniform elevated glucose that propagate with respect to a previously applied glucose gradient, as in A. (D) Proportion of calcium waves under uniform elevated glucose that propagate with respect to the preferred wave direction, where a gradient is previously applied toward or against the preferred direction. The dashed line indicates that the direction is solely determined by intrinsic cellular heterogeneity. Data in A and B were averaged over 22 islets. Data in C and D were averaged over 16 islets. ^∗∗∗ indicates significant difference comparing the indicated groups (p < 0.001 Student’s t-test). ns, no significant difference (p > 0.05). To see this figure in color, go online.