Organization of the core respiratory network: Insights from optogenetic and modeling studies
Fig 5
Effects of site-specific sustained photostimulation of inhibitory neurons within the pre-Bötzinger complex in situ.
(A-C) Examples of the effects of sustained stimulation (473 nm, 20 Hz, 20 ms pulses) of low (2.0 mW laser power in A) and higher intensity (4.0 mW in B and 5.0 mW in C). Representative traces of integrated phrenic nerve recordings (∫PN) are shown in the middle; the upper traces show the instantaneous inspiratory frequency (dots) and its low pass filtered time course (time-based moving median in a 3 s window, solid black line, the lower traces indicate the duration and amplitude of the sustained laser stimulation epoch. (D) Summary data (n = 10, mean ± SEM, **p<0.01, *p<0.05) of bilateral pre-BötC photostimulation shows that relatively weak (0.5–2.0 mW) stimulation significantly increased respiratory frequency in a laser power-dependent manner, and stronger (4.0–5.0 mW) stimulation caused a decrease of inspiratory frequency with complete termination of inspiratory activity for the stimulus duration at the maximum laser power (5.0 mW).