title: Anandamide levels in human female reproductive tissues: solid-phase extraction and measurement by ultraperformance liquid chromatography tandem mass spectrometry.
abstract: Anandamide (N-arachidonoylethanolamide), a bioactive lipid, is reported to play a role in pregnancy maintenance and parturition. Our aims were to (1) evaluate AEA levels at the human maternal:fetal interface and (2) validate the use of solid-phase extraction of AEA from tissues. AEA was analyzed in cord and maternal blood, amniotic fluid, placenta, and fetal membranes collected during Caesarean section (n=14). Extraction efficiencies were 42 and 36% for the placenta and the fetal membranes, respectively. Tissue AEA was quantified using an isotope-dilution method and UPLC-ESI-MS/MS giving intra- and inter-day variability for tissues spiked with 0.2, 1, and 5pmol/g AEA of less than 12%. Accuracy for these spiked samples was between 95% and 103% for fetal membranes and between 99% and 114% for placenta. Mean AEA concentrations were 2.72 + or - 1.04 pmol/g for placenta and 1.19 + or - 0.68 pmol/g for fetal membranes, and 0.93 + or - 0.28, 0.88 + or - 0.33, 0.77 + or - 0.30, and 0.06 + or - 0.04nM for maternal, umbilical vein, and umbilical artery plasma and amniotic fluid. Higher AEA concentrations were found in placenta compared to fetal membranes (P<0.0001), in umbilical vein compared with umbilical artery (P=0.0015), and in plasma from maternal circulation compared with umbilical artery (P=0.0152). The relevance of these changes in AEA concentrations at the maternal:fetal interface requires further investigation.
authors.affiliation: Endocannabinoid Research Group, Reproductive Sciences Section, Department of Cancer Studies and Molecular Medicine, University of Leicester, Robert Kilpatrick Clinical Sciences Building, Leicester Royal Infirmary, P.O. Box 65, Leicester, Leicestershire LE2 7LX, UK.
authors.forename: Timothy H
authors.initials: TH
authors.lastname: Marczylo
authors.forename: Patricia M W
authors.initials: PM
authors.lastname: Lam
authors.forename: Akwasi A
authors.initials: AA
authors.lastname: Amoako
authors.forename: Justin C
authors.initials: JC
authors.lastname: Konje
mesh_terms: D000653:Amniotic Fluid / Q000737:chemistry; D001095:Arachidonic Acids / Q000032:analysis* / Q000097:blood / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D063388:Endocannabinoids; D005321:Extraembryonic Membranes / Q000737:chemistry; D005260:Female; D006801:Humans; D010920:Placenta / Q000737:chemistry; D053284:Polyunsaturated Alkamides / Q000032:analysis* / Q000097:blood / Q000302:isolation & purification; D011247:Pregnancy; D052616:Solid Phase Extraction; D053719:Tandem Mass Spectrometry / Q000379:methods*; D014469:Umbilical Arteries / Q000737:chemistry; D014471:Umbilical Veins / Q000737:chemistry
chemical_list: D001095:Arachidonic Acids; D063388:Endocannabinoids; D053284:Polyunsaturated Alkamides; C078814:anandamide