Figure 6. Noradrenergic inhibition in cells depleted of either Gα_i or Gα_oA subunits.

A, superimposed Ca²⁺ current traces recorded in the absence and presence of noradrenaline (1 μM) in neurones preinjected intranuclearly with cDNA plasmids generating antisense RNA specific to Gα_q (a), Gα_oA (b) and Gα_i1-3 (c) subunits. Note the tonic facilitation (delineated by the dashed line) of basal I_Ca in the cell expressing Gα_oA antisense RNA (b). B, summary of calcium current inhibition (inhibition before (□) and after (▪) the conditioning depolarization) and ratio of inhibition (grey bars) in uninjected cells and cells expressing different Gα antisense RNAs. * P < 0.05; ** P < 0.005; *** P < 0.0001.