Figure 2.

Augmentation of Ca²⁺ channel currents in PC12 cells by hypoxia and AβPs. Mean (+s.e.m. bars) Ca²⁺ channel current–voltage (I–V) relationships obtained from PC12 cells in the absence (solid circles) and presence (open circles) of 200 μM Cd²⁺. (a) I–V relationships obtained from 20 control (normoxically cultured) cells. (b) I–V relationships obtained from 28 cells maintained in 10% O₂ for 24 h prior to recordings. (c) I–V relationships from nine cells exposed to 100 nM AβP_1–40 for 24 h prior to recording (also shown are mean data from 14 cells exposed to 20 nM AβP_1–40 for 24 h, in the absence of Cd²⁺; solid triangles). (d) I–V relationships from nine cells exposed to AβP_25–35 for 24 h. (e) Mean I–V relationships taken from hypoxically cultured cells, recorded in the presence of 200 μM Cd²⁺ (solid circles). Open circles show data from identically treated cells, except that they were exposed to the 3D6 antibody (5 μg ml⁻¹; 1 h). (f) As in (e), except that cells were exposed to amyloid petides (as in (c)) rather than hypoxia (n=8–15 cells in each case).