Glutamatergic neurotransmission is not essential for, but plays a modulatory role in, the production of gasping in arterially-perfused adult rat

Glutamatergic neurotransmission appears to be essential for generation of the eupneic pattern of inspiratory motor discharge as well as the expression of inspiratory-phase synchronization. The role of glutamatergic neurotransmission in the generation of gasping, including its accompanying modulation of spectral activity, is less well understood. The current investigation was, therefore, undertaken to investigate the effects of blockade of ionotropic glutamate receptors on (1) the generation and expression of gasping and (2) the magnitude and timing of spectral activity during gasping using an arterially-perfused decerebrate adult rat preparation. Our findings suggest that glutamatergic neurotransmission is not required for the production of gasping, but it may play a modulatory role in the expression of both the temporal and spectral characteristics of phrenic nerve discharge during gasping.