Figure 3. Phrenic nerve response to ischaemia in control and ethanol-exposed populations in situ.

A, recordings of integrated Phr nerve activity illustrating the absence of hyperventilation in ethanol-exposed animal and the earlier onset of gasping activity (single vertical arrows) due to shorter apnoea duration (horizontal arrows). During reoxygenation, recovery of eupnoeic activity was significantly delayed in the ethanol-exposed group (double arrows indicate first incrementing Phr burst). B, ethanol-exposed animals did not present a significant increase in Phr burst frequency and amplitude. ∫Phr: integrated phrenic nerve activity. Same statistical symbols as in Fig. 2. The simple arrow points to the first gasping burst and the double arrow to the first incrementing burst. Horizontal arrow delineates apnoea.