抄録
Effects of some prostaglandins (PGs) on adrenergic transmission were studied in guinea pig pulmonary arteries preloaded with 3H-norepinephrine. PGE1 and PGE2 at 0.1 to 100 nM concentration-dependently inhibited 3H-release and contraction evoked at 5 Hz. This inhibition was antagonized by diphloretin phosphate. PGF2α at 1 to 100 nM had no effect on evoked 3H-release and contraction. PGI2 at 1 to 100 nM also failed to modify evoked 3H-release, but markedly and concentration-dependently decreased evoked contraction. There exist presynaptic inhibitory PGE1 and PGE2 receptive sites on adrenergic neurons innervating guinea pig pulmonary arteries, whereas PGF2α and PGI2 produced no effect on the adrenergic neurons.
