title: Determination of prostaglandin precursors in frog tissue using selected-ion monitoring in gas chromatographic-mass spectrometric analysis.
abstract: Eicosatrienoic acid, eicosatetraenoic acid (arachidonic acid), and eicosapentaenoic acid are unsaturated fatty acids that are possible precursors for prostaglandin synthesis in amphibians. These compounds have been quantitatively identified in tissues of the American bullfrog by using methods of selected-ion monitoring for fatty acid methyl esters. Results from comparison of yield for four methylation techniques showed that boron trifluoride in methanol gave the best yield and reproducibility. Resolution values of 1.2 and 2.7 for these methyl esters were achieved by using a cyanosilicone liquid phase, and the limits of detection based on ion 79.1 a.m.u. were 0.5 ng absolute. These acids were extracted and methylated with overall recoveries of 47, 37 and 28%, respectively. Methyl esters were detected in extracts of all tissues in concentration ranges 12 to 912 ng/microliters of extract, or 30 to 2810 micrograms/g of tissue for 0.1- to 1.3-g samples.
mesh_terms: D000818:Animals; D005231:Fatty Acids, Unsaturated / Q000032:analysis* / Q000378:metabolism; D008401:Gas Chromatography-Mass Spectrometry; D009130:Muscle, Smooth / Q000378:metabolism*; D011453:Prostaglandins / Q000378:metabolism*; D011894:Rana pipiens; D012016:Reference Values
chemical_list: D005231:Fatty Acids, Unsaturated; D011453:Prostaglandins