title: Effects of leukotrienes C4, D4, and E4 on cerebral arteries of newborn pigs.
abstract: We examined effects of topical application of leukotrienes (LT) C4, D4, and E4 on cerebral arteries of newborn pigs in vivo. Diameters of pial arteries were measured using a cranial window method during application of artificial cerebrospinal fluid without drug, and cerebrospinal fluid containing LT C4, D4, and E4 (1, 10, 100, 1000, and 5000 ng/ml). Control diameters ranged from 51-345 micron. All three LT constricted pial arteries in a dose-dependent manner, with a threshold for detectable response at 10 ng/ml (7 +/- 3% for LTD4). The magnitude of constrictor response at the highest dose was 23 +/- 3% for LTC4, 17 +/- 2% for LTD4, and 17 +/- 3% for LTE4. The specific receptor antagonist FPL 55712 blocked the constrictor response to LT. We conclude that LT are potent constrictors of cerebral arteries in newborn pigs.
mesh_terms: D000818:Animals; D000831:Animals, Newborn / Q000502:physiology*; D002536:Cerebral Arteries / Q000187:drug effects* / Q000502:physiology; D002867:Chromones / Q000494:pharmacology; D003000:Clonidine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D017999:Leukotriene E4; D013189:SRS-A / Q000031:analogs & derivatives / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D013552:Swine; D014661:Vasoconstriction / Q000187:drug effects*
chemical_list: D002867:Chromones; D013189:SRS-A; D017999:Leukotriene E4; C006312:FPL 55712; D003000:Clonidine