Dose-dependent actions of @entity2918 (PGs) were investigated on cerebral arterial strips isolated from premature, newborn and adult @entity6599 . PGE1 an @entity1421 in low concentrations (10(-9) to 10(-7) M) elicited significant relaxation in both premature and newborn @entity3474 cerebral arteries. Arteries from adult @entity6599 showed slight or small relaxation in response to these PGs. @entity5015 and @entity1421 in higher concentrations (10(-8) to 10(-6) M) caused no contraction in premature and newborn arteries, but significant contraction in adult arteries. PGF2 alpha (10(-9) to 10(-7) M) elicited relaxations in arteries from @entity6599 of every age group, being greater in prematures and newborns than in adults. PGF2 alpha (3 X 10(-7) to 10(-5) M) produced a slight or small contraction in prematures and newborns, respectively, whereas larger contraction was induced in the adult artery. PGI2 ( @entity4770 ) (10(-8) to 10(-6) M) produced dose-dependent relaxation in arteries from @entity6599 of all age groups with no significant difference in the relaxant effect among the three age groups. Effective concentration (EC25) values for relaxant effect of PGE1 and @entity1421 were much less than those of PGF2 alpha and PGI2 in premature and newborn arteries. In adult cerebral arteries, only PGF2 alpha and PGI2 were effective in causing a significant relaxation. In premature and newborn arteries, PGE1 and @entity1421 were not effective in causing a significant contraction, whereas in adult arteries EC25 values for contractile effects of PGE1 and @entity1421 were less than those for PGF2 alpha.(ABSTRACT TRUNCATED AT 250 WORDS)

Relaxant and contractile responses to @entity2918 in premature, newborn and adult XXXX cerebral arteries.

@entity1421 :: ('MESH:D015232', 'Chemical') :: ['PGE2'] @entity3474 :: ('9555', 'Species') :: ['baboon'] @entity2918 :: ('MESH:D011453', 'Chemical') :: ['prostaglandins'] @entity4770 :: ('MESH:D011464', 'Chemical') :: ['prostacyclin'] @entity5015 :: ('MESH:D000527', 'Chemical') :: ['PGE1'] @entity6599 :: ('9557', 'Species') :: ['baboons']
@entity3474 :: (9555,Species) :: ['baboon']
