Figure 1.

The phasing of the pyloric CPG and the pacemaker kernel are strictly maintained over a range of physiological temperatures. A, Schematic connectivity diagram of the pyloric CPG (left) and isolated pyloric pacemaker kernel (right). The full network contains three motor neuron cell types (PD, LP, and PY) that burst sequentially in a rhythmic pattern to filter food particles in the pylorus. The phasing of this pattern is maintained over a physiological temperature range (Tang et al., 2010). The pacemaker kernel (yellow box) can be pharmacologically isolated by bath application of picrotoxin (PTX), which blocks a subset of inhibitory synapses (in purple). B, Isolated PD neuron bursting increases in frequency but maintains duty cycle in the face of temperature increases (previously published data from Rinberg et al., 2013). Traces in the left column show real-time traces. Traces on the right are normalized to cycle period. Bath temperature is indicated to the left of each trace and increases from cold (blue traces) to hot (red traces). The AB neuron is not shown, but fires in phase with PD. C, Quantification of pacemaker duty cycle as a function of temperature from Rinberg et al. (2013). Error bars represent mean ± SD.