Composition of O-alkyl and O-alk-1-enyl moieties in the glycerolipids of the human adrenal

A comparison of human adult and fetal adrenals with respect to their levels of glyceryl ether lipids and other lipid components is reported. Fetal glands contained significantly lower levels of alk-1-enyl phosphoglycerides and of cholesterol. Neutral glyceryl ether diesters, and ethanolamine and choline phosphoglycerides were isolated from adult adrenal tissue. The composition of the O-alkyl glycerol groups in these lipid fractions was obtained by means of gas chromatography of the trimethylsilyl ethers and diacetyl derivatives; O-alk-1-enyl glycerols were analyzed as their diacetates. About one-half of the alkyl and alk-1-enyl glycerol moieties present in glyceryl ether diesters contained hydrocarbon side chains with 20, 22, or 24 carbon atoms. Long hydrocarbon chains (C19-24) were also found in the O-alkyl glycerol moieties present in the total lipids of fetal adrenals.