Figure 9.

Functional characterization of MAB1/28 and Fab1 fragments in cAMP and [³⁵S]-GTPγ binding assays. Concentration–response curve of L-AP4 (A) and AMN082 (B) in the absence and presence of PTX in the CHO mGlu₇ expressing stable cell line 83. Cells were stimulated with 3 µmol·L⁻¹ forskolin, and various concentrations of L-AP4 or AMN082. Concentration–dependent inhibition of 300 µmol·L⁻¹ L-AP4 (C) and 1 µmol·L⁻¹ AMN082 (D) by MAB1/28, Fab1 fragments or LY341495 in the CHO line 83 cells. Cells were stimulated with 3 µmol·L⁻¹ forskolin, an EC₈₀ of L-AP4 or AMN082 and various concentrations of MAB1/28, Fab1 or LY341495. The cellular content of cAMP was measured and expressed as % cAMP content compared to cells treated with 3 µmol·L⁻¹ forskolin only. Concentration–response curves for L-AP4-induced [³⁵S]-GTPγ binding in the membranes from CHO mGlu₇ cell line 83, in the absence and in the presence of 3 nmol·L⁻¹ MAB1/28 (E) and in the absence and in the presence of 3 nmol·L⁻¹ Fab1 fragments (F). All measurements were performed in triplicate and values represent mean ± SEM.