TABLE 5.

pBFs comparing potency for ERK1/2 phosphorylation with calcitonin secretion, G_q/11 signaling, and [Ca²⁺]_i mobilization

The pBF of an agonist is calculated as the ratio between EC₅₀ between two different signaling pathways (pathway₁:pathway₂). However, for analysis of statistic difference between pBF of calcium and pBFs for all other agonists the negative logarithms of pBF or ppBF(pathway1:pathway2) = pEC₅₀(pathway1) − pEC₅₀(pathway2) were used. Statistical comparison of ppBFs for [Sr²⁺]_e to ppBFs of [Ca²⁺]_e was performed by using Student's t tests.

Agonist	pBF(ERK1/2:Calcitonin) (ppBF(ERK1/2:calcitonin) ± S.E.M.)	pBF(ERK1/2:[Ca2+]i) (ppBF(ERK1/2:[Ca2+]i) ± S.E.M.)	pBF(ERK1/2:IP1) (ppBF(ERK1/2:IP1) ± S.E.M.)
[Ca2+]e	1.2 (−0.095 ± 0.137)	2.1 (−0.315 ± 0.105)	0.63 (0.200 ± 0.056)
[Sr2+]e	0.51 (−0.292 ± 0.190)	0.13 (0.877 ± 0.150)**	0.049 (1.31 ± 0.14)**

^**, p < 0.01.