[Role of the vagus nerves in the respiratory rate changes in decerebrate cats].

Durations of respiratory cycle, of inspiration (TI), of expiration (TE) and tidal volume (VT) was measured. With vagus nerves intact increasing of lung ventilation was accompanied by increasing of breathing frequency (f) dependent on diminution of TI and TE. After bilateral vagotomy increasing of VT was accompanied by increasing of TE. In cases of well pronounced VT-TI relationship changes of f were determined by slope of contradictory changes of TI and TE. With increasing VT f could be constant or weakly increased or diminished. In cases of weak VT-TI relationship increase of VT was accompanied by f diminshing at the expense of TE increase. It is concluded that lungs mechanoreceptors cause f increment with VT increasing by 1) VT-TI curve displacement to left and down and 2) producing the linear relationship between TI and TE. After vagotomy TI and TE are determined by central mechanisms with certain degree of independence.