Rate of nitric oxide release in the lung and factors influencing
the concentration of exhaled nitric oxide.
Sato, Kunio, Tetsuo Sakamaki, Hiroyuki Sumino, Hironosuke Sakamoto,
Jin Hoshino, Hiroaki Masuda, Yoshie Sawada, Manabu Mochida, Yoshio
Ohyama, Toshiaki Kurashina, Tetsuya Nakamura, and Zenpei Ono.
The Second Department of Internal Medicine, Gunma University School
of Medicine, Maebashi, Japan 371
APStracts 2:0228L, 1995.
The level of nitric oxide (NO) in exhaled air fluctuates in normal
individuals depending on the physiological conditions. We evaluated
the effects of duration of exhalation and breath-holding on the
exhaled concentrations of NO in 16 normal human volunteers. Exhaled
gas corresponded to vital capacity was collected in 6 liter Tedlar
bags and analyzed by chemiluminescence. The NO concentration in
exhaled gas increased significantly in proportion to the duration of
exhalation (P = 0.009[umlaut]u}0.011, mean[umlaut]u}SD), and was
increased after breath-holding. There was no significant difference
in the exhaled NO concentration among 10 sec phases of a 30 sec
exhalation, as determined from multiple breath collections. The NO
released from the airways is presumably unaffected by fluctuation of
exhaling speed. The NO release rate, calculated from a single
regression analysis between the NO concentration and the duration of
exhalation, was 39[umlaut]u}29 pmol/sec, which value was about 4-fold
in 9 patients with bronchial asthma.
Received 27 November 1995; accepted in final form 6 December
1995.
APS Manuscript Number L342-5.
Article publication pending Am. J. Physiol. (Lung Cell. Mol.
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 23 December 95