Lipids

, Volume 25, Issue 9, pp 517–522

Tissue phospholipid fatty acid composition in genetically lean (Fa/−) or obese (fa/fa) zucker female rats on the same diet

  • Ph. Guesnet
  • J. -M. Bourre
  • M. Guerre-Millo
  • G. Pascal
  • G. Durand
Article

DOI: 10.1007/BF02537157

Cite this article as:
Guesnet, P., Bourre, J.M., Guerre-Millo, M. et al. Lipids (1990) 25: 517. doi:10.1007/BF02537157

Abstract

The fatty acid composition of serum total lipids, of phospholipids of various organs (liver, heart, kidney), and of nervous structures (brain, retina, sciatic nerve, myelin, synaptosomes) have been compared in lean (Fa/−) and genetically obese (fa/fa) Zucker female rats. Both received a standard commercial diet including 37% of 18∶2n−6 and 5% of n−3 polyunsaturated fatty acids (PUFA), 1.7% of which were in the form of 20∶5n−3 and 22∶6n−3. In comparison with lean rats, the results for the obese rats pointed out (i) no difference in the fatty acid composition of nervous structures: (ii) a decrease of 18∶2n−6 (from −8% to −35%) and of 20∶4n−6 (from −9% to −49%) in serum, liver and in kidney; this was compensated for by an increase in 20∶3n−6 (from +30% to +320%) and in total n−3 PUFA (from +68% to +76%); (iii) a decrease of 20∶4n−6 (−18%) and of 22∶6n−3 (−24%) in heart compensated for by an increase in 18∶2n−6 (+39%) and in 20∶3n−6 (+233%); and (iv) constant levels of total PUFA (n−6 and n−3) in the various fractions studied, except in serum where this level decreased (−23%). Finally, except for the nervous structures, tissue phospholipids of obese rats included a lower proportion of 20∶4n−6 and a higher proportion of 20∶3n−6. This resulted in a significant reduction in the 20∶4n−6/20∶3n−6 ratio; by contrast, the 20∶3n−6/18∶2n−6 ratio increased. The results suggest that in Zucker rats, the obese character (fa/fa) affects the desaturation-elongation process of 18∶2n−6 to 20∶4n−6 by specifically decreasing Δ5-desaturase activity.

Abbreviations

BHT

butylhydroxytoluene

GLC

gas-liquid chromatography

FFAP

free fatty acid phase

MUFA

monounsaturated fatty acids

PL

phospholipids

PUFA

polyunsaturated fatty acids

SFA

saturated fatty acids

TSL

total serum lipids

Copyright information

© American Oil Chemists’ Society 1990

Authors and Affiliations

  • Ph. Guesnet
    • 1
  • J. -M. Bourre
    • 3
  • M. Guerre-Millo
    • 4
  • G. Pascal
    • 2
  • G. Durand
    • 1
  1. 1.Station de Recherches de NutritionJouy-en-JosasFrance
  2. 2.Laboratorie des Sciences de la Consommation INRA-CRJJouy-en-JosasFrance
  3. 3.INSERM U26Hopital Femand-WidalParisFrance
  4. 4.INSERM U177Institut des CordeliersParisFrance