TABLE II.

Sparks Frequency and Morphology at Different [Ca²⁺]_SR

	Low Ca	High Ca	Δ	n
R	1.6781	2.0476	0.370a	10
SEM	0.0392	0.0812	0.087
f	4.8333	9.3429	4.510a	10
SEM	1.2816	1.7734	1.696
FWHM	1.5338	1.6200	0.086	7
SEM	0.0305	0.0417	0.039
Rise time	4.4653	4.9554	0.490	7
SEM	0.3572	0.2720	0.272
Amplitude	0.6584	0.6610	0.003	7
SEM	0.0234	0.0137	0.022

A “low Ca” and a “high Ca” value of the parameters listed were calculated for each fiber as described in the text. Column 4 (Δ) lists averages of fiber-paired differences, and their standard errors. n is number of experiments. Three fibers where f was very low (<1.0) were not included in the calculation of morphologic parameter averages.

^aSignificant difference.