Table 1.

Parameters derived from dose-response curves in the presence of varying external calcium concentrations

Ext. Ca2+ (mM)	I/I max	log EC50	EC50 (μM)	Hill slope	n
Wild type
0	1.01 ± 0.01	−6.11 ± 0.02	0.8	2.39 ± 0.18	11
1	0.85 ± 0.01	−5.68 ± 0.02	2.1	2.24 ± 0.19	11
3	0.76 ± 0.01	−5.61 ± 0.02	2.5	2.08 ± 0.19	6
10	0.6 ± 0.02	−5.55 ± 0.03	2.8	2.08 ± 0.26	6
E213Q
0	0.99 ± 0.01	−6.11 ± 0.02	0.8	2.45 ± 0.22	8
1	0.79 ± 0.01	−5.56 ± 0.01	2.8	2.39 ± 0.16	10
3	0.59 ± 0.01	−5.52 ± 0.02	3.0	2.42 ± 0.16	7
10	0.45 ± 0.02	−5.10 ± 0.04	7.9	1.62 ± 0.19	6
E215Q
0	1.00 ± 0.01	−6.05 ± 0.01	0.9	2.98 ± 0.11	8
1	0.74 ± 0.01	−5.82 ± 0.02	1.5	3.09 ± 0.39	7
3	0.71 ± 0.01	−5.66 ± 0.01	2.2	2.54 ± 0.19	10
10	0.64 ± 0.02	−5.48 ± 0.03	3.3	1.90 ± 0.24	7
E277A/S297R
0	1.00 ± 0.01	−5.77 ± 0.02	1.7	2.04 ± 0.16	4
1	1.00 ± 0.02	−5.55 ± 0.04	2.8	1.64 ± 0.25	4
3	0.99 ± 0.03*	−5.72 ± 0.07	1.9	1.62 ± 0.30	6
10	0.96 ± 0.02*	−5.54 ± 0.04	2.9	1.35 ± 0.18	4

Data = mean ± SEM.

^*Sig. dif. (P < 0.05) to wild type at the same calcium concentration.