We describe a micropipette method for obtaining secretions from single submucosal gland ducts in vivo in cat tracheas. The secretory rate of 65 glands sampled under basal conditions in 16 animals varied from 3 to 30 nl/min (mean ± SE, 9.05 ± 0.60 nl/min) and varied 2- to 3-fold among glands sampled within an animal. Sequential samples collected from individual ducts during a 10-min period were highly repeatable (correlation coefficient, 0.96) and were remarkably constant for as long as 4 h. Vagal cooling decreased the secretory rate by a mean of 39% (n = 11, p < 0.05). Stimulation of the cervical vagus nerves increased flow from 8.3 ± 0.7 to 16.4 ± 0.8 nl/min (n = 15, p < 0.01), an effect that was abolished by intravenous injection of 0.5 mg of atropine sulfate/kg of body weight or by cooling of the vagus nerves, but not by 0.08 mg of phentolamine/kg given intravenously. Intravenous injection of 0.3 mg of phenylephrine/kg of body weight increased flow from 8.6 ± 0.6 to 18.9 ± 1.1 nl/min (n = 20, p < 0.001), an effect that was prevented by phentolamine, but not by atropine. We conclude that cholinergic and α-adrenergic stimulation increases fluid secretion from feline submucosal glands.
|Original language||English (US)|
|Number of pages||7|
|Journal||American Review of Respiratory Disease|
|Publication status||Published - Jan 1 1980|
ASJC Scopus subject areas
- Pulmonary and Respiratory Medicine