[Respiratory regulations of pulmonary vagal nerves under hypercapnic conditions; effects of J-receptor].
We studied ventilatory responses under hypercapnic condition in 9 lightly anesthetized dogs, using a vagal nerve cooling technique. One side of the cervical vagosympathetic trunks of dogs were previously severed, and a copper cooler was attached to the other side. When the cervical nerve was cooled below 7 degrees C, the Hering-Breuer inflation reflex ceased. We found that when the vagal nerve was not cooled or cooled to 7 degrees C, the respiratory frequency increased significantly in relation to hypercapnic gas inhalation. However, the increment of respiratory frequency was reduced by bilateral cervical vagotomy. We concluded that the J-receptor is responsible for the increase in respiratory frequency under hypercapnic gas inhalation.
Sagara
Y
Y
Isogami
K
K
Saito
H
H
Ono
S
S
Sakuma
T
T
Koike
K
K
Nakata
T
T
D000818:Animals; D002245:Carbon Dioxide / Q000502:physiology*; D004285:Dogs; D008168:Lung / Q000294:innervation*; D012018:Reflex; D012119:Respiration; D011984:Sensory Receptor Cells / Q000502:physiology*; D014630:Vagus Nerve / Q000502:physiology*
D002245:Carbon Dioxide