Statistics.
Statistical analysis was performed with SPSS 20.0 computer software
(SPSS Inc., Chicago, IL, USA). To compare the quantitative variables,
the Student’s t-test was used. Cytosolic Ca 2+ was analyzed using a
one-way analysis of variance followed by multiple Tukey-Kramer
comparisons. Data are expressed as the mean and the standard deviation.
A p level lower than 0.05 was used to indicate a significant difference.