Figure 5. β₁γ₂ overexpression specifically occludes PTX-sensitive inhibition.

A and B, prepulse I_Ca amplitude (○) and facilitation (♦) plotted as a function of time in a control neurone (A; preinjected with 800 μg ml⁻¹γ₂ construct, 31 pF) and in a neurone co-expressing β₁ and γ₂ subunits (B; 400 μg ml⁻¹ each of β₁ and γ₂ constructs, denoted β₁γ₂, 40 pF). Horizontal bars indicate the time and duration of application of somatostatin (50 nm), noradrenaline (300 nm) and angiotensin II (500 nm). The lower panel in B shows superimposed I_Ca traces selected before (open arrows) and during (filled arrows) application of agonists as indicated in the upper panel in B. I_Ca was recorded using the perforated-patch method and evoked using the double voltage pulse as illustrated in Fig. 1. Cells were recorded 24 h after injection.