The effects of lipoxygenase metabolites of arachidonic acid on human myometrial contractility.
The effects of the lipoxygenase products of arachidonic acid, 5- and 12-hydroxyeicosatetraenoic acid (5- and 12-HETE) and leukotriene B4 (LTB4), on the spontaneous contractility of lower uterine segment human myometrial strips obtained prior to labour have been studied in vitro. 5-HETE gave a dose- dependent (10-500ng) increase in both the rate of contractions and overall contractility of myometrial strips while 12-HETE and LTB4 had no effect at the same concentrations. Prostaglandin F2 alpha (50ng) contracted all myometrial strips in a similar pattern to 5-HETE but was approximately 10 times more potent. The effect of 5-HETE may be direct or perhaps indirect via interaction with the cyclo-oxygenase pathway. The findings do not disprove the contention that the onset of parturition may be characterised by a switch in arachidonic acid metabolism in intra-uterine tissues from lipoxygenase to cyclo-oxygenase products.
Bennett
P R
PR
Institute of Obstetrics and Gynaecology, Hammersmith Hospital, London, England.
Elder
M G
MG
Myatt
L
L
D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism; D005260:Female; D006801:Humans; D006893:Hydroxyeicosatetraenoic Acids / Q000494:pharmacology*; D007743:Labor, Obstetric / Q000378:metabolism; D007975:Leukotriene B4 / Q000494:pharmacology*; D011247:Pregnancy; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism; D014590:Uterine Contraction / Q000187:drug effects*
D001095:Arachidonic Acids; D006893:Hydroxyeicosatetraenoic Acids; D007975:Leukotriene B4; D016718:Arachidonic Acid; C022022:5-hydroxy-6,8,11,14-eicosatetraenoic acid; D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; D011451:Prostaglandin-Endoperoxide Synthases