[Relationship between duration of expiration and depth of breathing in decerbrate cats].

In decerbrated cats, tidal volume (Vt) increased from apnoea to maximal values in result of rebreathing. With vagus nerves intact increment of Vt was accompanied by shortening of both inspiratory (Ti) and expiratory (Te) phases. Relationship Te vs. Ti was mainly linear. Decrease of Te with progressing hyperpnoea was determined by impulses from lungs mechanoreceptors. After vagotomy Vt increase was accompanied by increment of Te. Bulbopontine respiratory mechanism reacted to chemical stimuli by increasing Te. The constant relationship between Ti and duration of the next expiration was disappeared.