Journal of Applied Physiology, Vol 71, Issue 3 939-944, Copyright © 1991 by American Physiological Society
Neural regulation of lysozyme secretion from tracheal submucosal glands of ferrets in vivo
B. Davis and H. C. Tseng
Cardiovascular Research Institute, University of California, San Francisco 94143-0130.
To investigate how central and peripheral nerves affect lysozyme secretion
from tracheal submucosal glands in ferrets we injected substance P (20
nmol/kg in 200 microliters) intracisternally or intravenously into
anesthetized artificially ventilated ferrets. We collected 3-ml samples
from a perfused (3 ml/5 min) segment of trachea in situ during 15 min
before and 45 min after injection of substance P. Content of lysozyme, a
specific marker of tracheal submucosal gland serous cell secretion in
ferrets, was measured spectrophotometrically in each sample. Intracisternal
substance P increased peak lysozyme output threefold compared with
baseline. This increase was abolished completely by cutting both superior
laryngeal nerves (SLN) and was partially inhibited by atropine,
phentolamine, or propranolol. Intravenous substance P increased peak
lysozyme output 10-fold compared with baseline. This increase was partly
abolished by cutting both SLN. We concluded that intracisternal substance P
stimulated the central nervous system (CNS) and activated cholinergic,
adrenergic, and nonadrenergic noncholinergic secretomotor nerves to
tracheal glands and that intravenous substance P increased lysozyme
secretion both by acting directly on tracheal glands and indirectly on the
CNS to activate secretomotor nerves.
