Table 1.

Effect of calcium ion on [³H]taurine efflux in TR-TBT cells

Condition	Intracellular amount of [3H]taurine remained (% of time 0)
	TR-TBT 18d-1	TR-TBT 18d-2
Control	100 ± 2	100 ± 3
Ca2+ free	72.1 ± 3.3 **	75.7 ± 4.5 **

Cells were incubated for 60 min at 37°C with ECF buffer containing [³H]taurine (28 nM). The cells were washed and then incubated with ECF buffer or Ca²⁺ free buffer for 30 min Under Ca²⁺ free condition, Ca²⁺ was replaced with Mg²⁺. Remaining of [³H]taurine in the cells was measured. Each value represents the mean ± SEM (n=3-4). ^** p<0.01 significantly different from normal efflux.