Figure 1.

Prolonged PCB-95 exposure attenuates electrically evoked Ca²⁺ signals in cultured hippocampal neurons. (A) Representative Ca²⁺ transients produced by 9-DIV (days in vitro) neurons in response to electrical stimuli applied at increasing frequency (10-sec duration at 6 V). Neurons were loaded with Fluo-4 after 48-hr treatment with either vehicle or PCB-95. (B) Prolonged exposure to PCB-95 decreased the amplitude of electrically evoked Ca²⁺ transients in a concentration-dependent manner. AFU, arbitrary fluorescent units. Data are presented as mean ± SE (n = 10–12 neurons from three independent dissections). p < 0.05 relative to vehicle control for all treatment groups.