![electrical gradient electrical gradient](https://pubs.rsc.org/image/article/2014/cp/c4cp01180e/c4cp01180e-f10_hi-res.gif)
#Electrical gradient code#
The colour code depicts the timing of activation. c, e, i, Isochronal maps of Bay-K 8644- ( c) and thapsigargin+caffeine- ( e) –treated hearts and the heart of an embryo injected with 25 µg/µl of clmc2::wnt11:CFP ( i). One-way ANOVA for comparisons with wildtype, *p<0.05. Error bars depict SEM.Ī, Averaged Ca 2+ transients from ROIs in Figure 3 b, c and Supplementary Figure 5 c, d. j, Mean ventricular cardiomyocyte circularity index and cell area from wildtype (n=4) and silent heart embryos (n=4). h, i, Z projection of 1µm confocal section from a wild-type heart ( h) and silent heart ( i) stained with anti-β-catenin. g, Average fluorescence intensities of respective ROIs from Cx43-stained hearts (n=10). The arrowhead points to outflow tract cardiomyocytes with slightly elevated Cx43 levels. f, Z projection of 2µm confocal section from a wild-type heart stained with anti-Cx43. e, Upstrokes (grey) and derived upstroke velocities (black) of action potentials in d. d, Averaged action potentials (n=5) from OC and IC ROIs at 72hpf. c, Mean estimated conduction velocities from ROIs in a and b.
![electrical gradient electrical gradient](https://gbmedia.azureedge.net/aza/user/gear/suhr-modern-sparkle-desert-gradient.jpg)
The red arrows represent the average velocity vectors: an integral of the mean direction and speed of electrical impulse propagation, in the corresponding ROI. Squares indicate regions of interest (ROI) for conduction velocity estimation. The colour code depicts the timing of electrical activation (blue areas activated before red areas). Each line represents the action potential wavefront position at 5 ms intervals. The regulation of cellular coupling through such mechanisms may be a general property of non-canonical Wnt signals.Ī, b, Isochronal maps of wildtype hearts at 24hpf ( a) and 72hpf ( b). These data reveal a previously unrecognized role for Wnt/Ca(2+) signalling in establishing an electrical gradient in the plane of the developing cardiac epithelium through modulation of ion-channel function. Although the traditional planar cell polarity pathway is not involved, we obtained evidence that Wnt11 acts to set up this gradient of electrical coupling through effects on transmembrane Ca(2+) conductance mediated by the L-type calcium channel. We excluded a role for differences in cellular excitability, connexin localization, tissue geometry and mechanical inputs, but in contrast we were able to demonstrate that non-canonical Wnt11 signals are required for the genesis of this myocardial electrical gradient. Here we identify a gradient of electrical coupling across the developing ventricular myocardium using high-speed optical mapping of transmembrane potentials and calcium concentrations in the zebrafish heart. The fundamental mechanisms that regulate the establishment and maintenance of such electrical polarities are poorly understood. The electric field can then be writtenĮxpressions of the gradient in other coordinate systems are often convenient for taking advantage of the symmetry of a given physical problem.Electrical gradients are critical for many biological processes, including the normal function of excitable tissues, left-right patterning, organogenesis and wound healing. This collection of partial derivatives is called the gradient, and is represented by the symbol ∇. The expression of electric field in terms of voltage can be expressed in the vector form HyperPhysics***** Electricity and Magnetism The electric field can then be expressed asįor rectangular coordinates, the components of the electric field are If the differential voltage change is calculated along a direction ds, then it is seen to be equal to the electric field component in that direction times the distance ds. The component of electric field in any direction is the negative of rate of change of the potential in that direction. One of the values of calculating the scalar electric potential ( voltage) is that the electricfield can be calculated from it. Electric Field from Voltage Electric Field from Voltage