TABLE 2.

Comparison of the permeabilities of the plasma membrane to Ca²⁺, Ba²⁺, and Sr²⁺ in mock-and rotavirus-infected MA104 cells^a

Infection	Cation	[Cation2+]i change		Time to d [Cation2+]i/ dtmax (s)	n
		Δ amplitude at 20 s (nM)	d[Cation2+]i/ dtmax (nM/s)
Mock	Ca2+	44 ± 3	7.7 ± 0.5	9.8 ± 0.8	4
	Ba2+	431 ± 63	77.8 ± 15.3	9.0 ± 0.1	3
	Sr2+	365 ± 92	113.0 ± 18.6	9.0 ± 0.7	3
Virus	Ca2+	228 ± 23*	48.0 ± 4.7*	11.3 ± 1.9†	4
	Ba2+	1,226 ± 144*	298.8 ± 92.2*	10.7 ± 1.7†	3
	Sr2+	894 ± 55*	204.7 ± 34.9*	11.7 ± 2.2†	3

^aAt 7 h postinfection, changes in intracellular cation concentration in mock- and rotavirus-infected MA104 cells were measured as detailed in the legend to Fig. 6. The change in intracellular cation concentration was determined in each individual experiment at 20 s after a 5 mM change in extracellular cation concentration (Δ amplitude). The peak value of the first derivative of the original traces corresponds to the maximal rate of [Cation²⁺]_i increase after cation addition (d[Cation²⁺]_i/dt_max). The time from the cation addition to attain this last value was computer determined in each experiment from derivative curves like the ones shown in Fig. 6. Values are means ± SEMs from n experiments in each case. *, significantly different from the corresponding value for mock-infected cells by the Mann-Whitney test (P < 0.05); †, not significantly different from the corresponding value for mock-infected cells.