Fig. 1.

BDNF increases respiratory frequency in the fetal mouse transverse brainstem slice preparation. Integrated population activity recorded from the preBötC respiratory network in control conditions (A) and after 15 min (B) and 30 min (C) exposure to 100 ng/mL BDNF. (A) Top: Schematic diagram of a transverse brainstem slice containing the preBötC from which population activity was recorded (see the integrated trace below). (D) Graph representing the kinetics of BDNF effects on individual burst frequency (black dots) and on frequency average/min (green dots) recorded from a single preparation. Grey rectangles indicate the time window during which measurements were performed for every experiment. (E) Bar histogram depicting the mean frequency of the preBötC rhythmic activity obtained from 13 preparations; control (CTL) (white bar), BDNF (15 and 30 min; two black bars) and nerve growth factor (NGF) (100 ng/mL; grey bar; n = 6). BDNF induced a significant increase in the frequency of the preBötC population activity, whereas NGF had no effect (*P < 0.05). IO, inferior olive; XII, hypoglossal nucleus; NA, nucleus ambiguous; D, dorsal; Int, integrated; IV, fourth (ventrical); V, ventral; ns, not significant.