pge ( 2 ) , pga ( 1 ) or pga ( 2 ) produced only weak superimposed contractions.4 in contrast to intrapulmonary arteries , intrapulmonary veins contracted in a concentration-related fashion to all prostaglandins tested , where the contractile sensitivity was ( based on ec ( 50 ) s and threshold concentrations ) : pgb ( 2 ) > pgb ( 1 ) > pgd ( 2 ) > pgf ( 2alpha ) > pga ( 2 ) > > pga ( 1 ) > pgf ( 1alpha ) > pge ( 2 ) > pge ( 1 ) .5 in terms of the ability to generate maximum contractile responses on intrapulmonary veins , the prostaglandins were also variable , with pga ( 2 ) and pgb ( 2 ) being the most potent and pgd ( 2 ) the least potent.6 intrapulmonary veins , partially contracted by 5-ht , exhibited concentration-related relaxations to pge ( 1 ) at low concentrations , followed by secondary contractile responses at higher concentrations.7 neither pga ( 1 ) nor pga ( 2 ) ( 3.4 x 10 ( -8 ) to 3.4 x 10 ( -5 ) m ) inhibited or potentiated 5-ht responses of intrapulmonary arteries.8 these data suggest that there are species , regional and major qualitative and quantitative , differences in the responsiveness of intrapulmonary arteries and veins to prostaglandin .
C0033557
pgb
C0033554
prostaglandin