Decreases in the diameter ratio increases the rate of tapering, and reduces the diameter of every compartment except the first. The period of oscillation for the coupled model is shown in red. With increased tapering, the smaller compartments were overcome by the larger currents that could be generated by the larger ones, and the coupled system was increasingly dominated by the largest compartments. Figure 7 Measurement of calcium transients and steady state values in voltage clamp experiments. The cell was identified by its position, morphology, and spontaneous electrical activity before voltage clamp recordings were begun.
Boxes indicate positions of integrated calcium measurements.
Calcium levels increase approximately exponentially at the start of the voltage step. Calcium accumulation is more rapid in the dendrite than in the soma, but the steady state values for the two are similar. Calcium levels decay more slowly in the soma than the dendrite. Figure 8 Steady state calcium concentration measurements can be used to measure the voltage sensitivity of the calcium current. The equation for the calcium nullcline is that for the simplified one compartment model.