Table 2.

Effect of AP repolarization on simultaneously measured I_Ca,L and CaTs

	Epi Template (n = 5)		PM Template (n = 5)
	Control	Intracellular acidosis	Control	Intracellular acidosis
Initial peak ICa,L, pA/pF	−7.64 ± 0.59	−5.35 ± 0.70**	−4.24 ± 0.14##	−3.91 ± 0.14*
Net Ca2+ influx via ICa,L, pC/pF	0.31 ± 0.03	0.40 ± 0.05*	0.23 ± 0.02	0.27 ± 0.03*
CaT amplitude (F/F0)	1.95 ± 0.23	2.09 ± 0.23**	1.53 ± 0.07	1.55 ± 0.06
Rate of rise, F/F0/s	51.8 ± 16.4	65.2 ± 14.4*	32.4 ± 6.55	33.3 ± 2.49
E-C coupling gain, (F/F0/s)/(pA/pF)	7.36 ± 2.66	13.8 ± 4.22*	7.69 ± 1.60	8.58 ± 0.79

All values are means ± SE. All experiments were performed in the absence of acidosis with appropriate action potential (AP) templates for control and intracellular acidosis. I_Ca,L, L-type calcium current; CaT, calcium transient; Epi, epicardial; PM, papillary muscle; F/F₀, ratio of fluorescence during CaT divided by diastolic fluorescence; E-C, excitation-contraction.

^*P < 0.05,

^**P < 0.01 vs. control, paired; ^##P < 0.01 vs. control with Epi template, unpaired.