Js. Lacroix et al., POSTEXERCISE NASAL VASOCONSTRICTION AND HYPOREACTIVITY - POSSIBLE INVOLVEMENT OF NEUROPEPTIDE-Y, Acta oto-laryngologica, 117(4), 1997, pp. 609-613
Neuropeptide Y (NPY) is co-localized with noradrenaline (NA) in periva
scular sympathetic nerve and is a vasoconstrictor. Pre-treatment with
exogenous NPY markedly reduced nasal airway obstruction and rhinorrhea
induced by the irritant capsaicin in control subjects. The aim of the
present experiments was to study the time course variations of plasma
concentrations of NA and NPY during and after intense exercise in 17
healthy volunteers. In parallel, changes in nasal airway resistance (N
AR) were recorded. Nasal obstruction and rhinorrhea induced by capsaic
in were compared after 30 min of rest and after 30 min of exercise. Bo
th subjective and objective NAR were significantly reduced (p < 0.05)
for over 15 min after the end of exercise. Plasma levels of NPY remain
ed increased for more than 15 min after exercise whereas NA returned t
o basal values within less than 10 min. The increases of NAR and mucus
production evoked by capsaicin were markedly attenuated for 30 min af
ter exercise (p < 0.05). Variations of plasma NPY concentrations over
time correlated better with post-exercise nasal vasoconstriction and h
yporeactivity to capsaicin than NA. These observations suggest that en
dogenous NPY could be involved in the prolonged post-exercise nasal va
soconstriction and acts as a modulator of nasal airways reactivity.