AJP - Heart and Circulatory Physiology, Vol 241, Issue 5 756-H759, Copyright © 1981 by American Physiological Society
Perinatal pulmonary prostaglandin production
C. W. Leffler and J. R. Hessler
Products of reactions catalyzed by prostaglandin cyclo-oxygenase
[prostaglandins (PG), thromboxanes] were analyzed by gas chromatography
with electron-capture detection in the venous effluents of in situ
Krebs-perfused lungs of exteriorized fetal goats and sheep before and after
ventilation with air. The major products were 6-keto-PGF1 alpha and
6,15-diketo[13,14-dihydro] PGI2 without blood components. After
ventilation, which decreased pulmonary vascular resistance to 63% of the
before-ventilation value, lung production of 6-keto-PGF1 alpha and
metabolite increased 50 and 230%, respectively. These data, in addition to
earlier findings of inhibition of ventilation-induced pulmonary
vasodilation by indomethacin and increased net production of PG-like
material after ventilation of blood-perfused fetal lungs, support the
hypothesis that ventilation of fetal lungs with air at birth increases
synthesis of PGI2 by or near pulmonary resistance vessels, resulting in
high local concentrations of PGI2 near its site of production. PGI2 appears
to be important in the pulmonary vascular resistance decrease that is
necessary for successful perinatal transition.
