Journal of Applied Physiology, Vol 47, Issue 2 285-289, Copyright © 1979 by American Physiological Society
Dibutyryl cyclic GMP and hyperventilation promote rat lung phospholipid release
D. J. Klass
Ventilation of rats at high inspiratory pressures raises lung tissue
content of guanosine 3',5'-cyclic monophosphate (cGMP). Hyperventilation in
rabbits augments release of phospholipid into lavage fluid. Can cGMP, in
the absence of hyperventilation, increase lung phospholipid release?
Sprague-Dawley rats are injected with [14C]palmitate, and after 1.5 h are
anesthetized and ventilated for 20 min. Three groups are ventilated at peak
inspiratory pressures (PIP) of 10 cmH2O, while saline, dibutyryl adenosine
3',5'-cyclic monophosphate (DBcAMP), or dibutyryl cGMP (DBcGMP) is infused
into the pulmonary artery. In a fourth group, saline is infused into the
pulmonary artery, but ventilation is performed with PIP of 25 cmH2O. Lung
tissue and lavage fluid are then analyzed for phospholipid (PL) content and
for incorporation of [14C]palmitate into lavage and tissue PL fractions.
Ventilation at increased pressure and infusion of DBcGMP are associated
with increases in release of labeled PL into lavage fraction. The findings
suggest that the increase in lavage PL release associated with
hyperventilation is, at least in part, mediated by cGMP.
