Reactiions of the breathing pattern to microinjections of bicuculline into the Botzinger and pre-Botzinger complex in rats

Microinjections of selective GABAА-antagonist bicuculline (10-6 M) into Bötzinger complex (BC) and pre-Bötzinger complex (PBC) in mature rats caused the respiratory changes. In particular, the injections into BC extended both the inspiratory and expiratory time while after the injections into PBC only expiratory time was extended. When bicuculline injected into PBC, tidal volume increased while injections of bicuculine into BC did not induce any significant change in tidal volume. The respiratory effects of bicuculline demonstrate the various role of GABAА-receptors at the BC and PBC level in the control of temporal and volume respiratory pattern parameters.