Figure 5.
Inspiratory motor output in the rhythmic slice in vitro depends on endogenous activation of 5-HT2A and NK-1 receptors. Bath application of methysergide (MeSG, n = 9), ketanserin (KET, n = 8), MDL 11,939 (n = 6), RS 102221 (n = 7), GR 113808 (n = 3), and SR 140333 (n = 7) produced a concentration-dependent depression of baseline inspiratory activity (monitored by recordings of integrated XII motoneuron population activity), with a reversible reduction in the inspiratory XII burst frequency (left) and burst amplitude (right). Panels show steady-state dose–response relations normalized to control. Amplitudes are measured from the peak of the integrated XII population activity. Data points represent mean values ± SEM.