Central and Peripheral GABA_A Receptor Regulation of the Heart Rate Depends on the Conscious State of the Animal

Figure 4

Effect of diazepam on isolated retrograde perfused female guinea pig hearts (868±45 g). After a minimum of 30 min stabilization, the hearts underwent 20 min of baseline recording. Subsequently the hearts were exposed to diazepam at increasing concentrations in 20 min intervals. Diazepam induced a dose-dependent reduction of heart rate and significantly shortened the heart rate at 30 μM (𝑛=5).