title: (n-3) and (n-6) polyunsaturated fatty acids in the phosphoglycerides of salt-secreting epithelia from two marine fish species.
abstract: Fatty acid analyses were carried out on phosphoglycerides isolated from microsomal fractions of the rectal gland of the dogfish,Scyliorthinus canicula, and gills of the cod,Gadus morhua. Ratios of (n-3)/(n-6) polyunsaturated fatty acids were ca. 10 for phosphatidylcholine, (PC), phosphatidylethanolamine (PE) and phosphatidylserine (PS) from cod gills, reflecting high concentrations of 20∶5 (n-3) and 22∶6(n-3). The ratio for phosphatidylinositol (PI) from cod gills was 1.3, reflecting high concentrations of 20∶4(n-6) as well as (n-3) polyunsaturates. PC, PE and PS from rectal glands all had much lower (n-3)/(n-6) ratios than in cod gills, reflecting higher concentrations of 20∶4(n-6), but the lowest ratio was again present in PI. The latter phospholipid had high concentrations of 18∶0 in both tissues. The relative constancy of the fatty acid composition of PI in the two salt-secreting tissues and its similarity to mammalian phospholipids is considered to reflect its specialized role in biomembranes.
authors: Natural Environment Research Council, Institute of Marine Biochemistry, St. Fittick's Road, AB1 3RA, Aberdeen, UK.
authors: M V
authors: MV
authors: Bell
authors: Natural Environment Research Council, Institute of Marine Biochemistry, St. Fittick's Road, AB1 3RA, Aberdeen, UK.
authors: C M
authors: CM
authors: Simpson
authors: Natural Environment Research Council, Institute of Marine Biochemistry, St. Fittick's Road, AB1 3RA, Aberdeen, UK.
authors: J R
authors: JR
authors: Sargent