[Effects of microinjection of amino acids into pre-Bötzinger complex on respiration in adult rats]

Experiments were performed on sodium pentobarbital anesthetized and bilaterally vagotomized adult SD rats. Microinjection of an excitatory neurotoxin, kainic acid, into pre-Bötzinger complex initially lengthened the duration of inspiration, shortened the duration of expiration and increased the respiratory frequency, and subsequently abolished rhythmic respiration. Injection of an excitatory amino acid, L-glutamate, shortened the duration of expiration. Injection of the inhibitory amino acids (either glycine or gamma-aminobutyric acid) shortened the duration of inspiration. These results suggest that the pre-Bötzinger complex in adult rats plays an important role in neurogenesis and maintenance of rhythmic respiration.