Figure 5. LDL promotes non-uniform Ca²⁺ - transients at short stimulation intervals.

A Calcium transients recorded at stimulation intervals of 2.5, 2, 1.5, 1 and 0.75 s (top to bottom) in the absence (CONTROL) or the presence of 500 µg/ml LDL (right panel). Each stimulation pulse is indicated with a dot above the traces. B Representative traces illustrating uniform, alternating and irregular response. C Distribution of uniform (black bar), alternating (grey bar) or irregular (white bar) calcium transient amplitudes at decreasing stimulation intervals recorded in the absence (CONTROL) or the presence of 500 µg/ml LDL (right panel). Values were recorded in four different fields from each of five HL-1 preparations.