Fig. 9: Spontaneously active β3-containing receptors reduce neuronal excitability.
From: Structural determinants and regulation of spontaneous activity in GABAA receptors
a Current clamp recordings from hippocampal neurons expressing eGFP, β3, β3DNTK or β3K279T during injection of depolarising constant current steps of increasing amplitude (20 pA increments). b Rheobase determination for hippocampal neurons transfected with eGFP, β3 or β3DNTK cDNAs. Neurons expressing β3DNTK showed rheobase values similar to eGFP control (P = 1), while β3-transfected neurons were less excitable, as demonstrated by higher rheobase values than eGFP (**P = 0.0026) and β3DNTK-transfected (*P = 0.042) neurons. Expression of the highly spontaneous β3K279T resulted in 7 of 8 neurons unable to evoke action potentials. The one excitable cell had a rheobase of 220 pA (not shown). The input–output curves are shown in c. Kruskal–Wallis with Dunn’s post-hoc test were used to compared rheobase values (eGFP: n = 11; β3DNTK: n = 7; β3: n = 10; β3K279T: n = 8). Data are presented as mean values ± SEM. *P < 0.05; **P < 0.01; ns no significance. Source data are provided as a Source Data file for Fig. 9.
