Prostaglandin E1 and E2 in bovine semen: Quantification by gas chromatography

Prostaglandins PGE₁ and PGE₂ extracted from bovine semen, purified via silicic column chromatography were quantified by gas chromatography as their methoxime methyl ester trimethylsilyl ether derivatives. The PGE₁ and PGE₂ concentrations of 19 bovine semen samples ranged from 395 ± 225 and 487 ± 407 ng/ml, respectively. A constant 1:1 ratio between PGE₁ and PGE₂ was observed. There was no relationship between PGE and sperm motility, but high sperm counts were generally associated with decreased PGE levels. The direct precursors of PGE₁ and PGE₂, i.e. 20:3n6 and 20:4n6, occurred in low concentrations compared to other related unsaturated fatty acids, i.e. 18:2n6 and 22:5n6 of the n-6 family.