Table 4.

Levels of R-568-induced ΔI_sc in forskolin-stimulated colon at different Ca_o²⁺ conditions

	ΔIsR-568, μA/cm2
	Absence of TTX		Presence of TTX
	Proximal	Distal	Proximal	Distal
Cao2+ = 0.5 mM	56 ± 14 (9)	37 ± 8 (9)	9 ± 4 (8)	6 ± 2 (8)
Cao2+ = 1.25 mM	28 ± 11 (6)ns	30 ± 10 (6)ns	1 ± 1 (4)ns	2 ± 1 (4)ns

Data shown are means ± SE (n). ΔI_sc^R-568, R-568-induced ΔI_sc. ns, P > 0.05 vs. Ca_o²⁺ = 0.5 mM.