Effect of maternal dietary fats with variable n-3/n-6 ratios on tissue fatty acid composition in suckling mice.
This report examines the distribution of n-3 and n-6 fatty acids in heart, kidney and liver phosphatidylcholine and phosphatidylethanolamine of suckling mice from dams fed a fat-supplemented diet with variable n-3/n-6 ratios. After conception and throughout the pregnancy and lactation period, dams were fed a fat-free liquid diet supplemented with 20% by energy of oil mixtures (fish oil concentrate, rich in 20:5n-3 and 22:6n-3, and safflower oil concentrate, rich in 18:2n-6). The diets contained similar amounts of combined n-3 and n-6 fatty acids but variable ratios of n-3 to n-6 fatty acids (0, 0.25, 0.5, 1, 2 and 4). In 12-day-old suckling mice, as the n-3/n-6 ratio in the maternal diet increased (up to approx. 0.5), the tissue levels of 20:5n-3, 22:5n-3 and 22:6n-3 increased, whereas those of 18:2n-6 and 20:4n-6 decreased. The responses were similar in both phospholipid subclasses, but varied between different tissues. Generally, the n-3/n-6 ratios were significantly greater in pup tissues than in milk fat, indicating preferential incorporation of n-3 over n-6 fatty acids into phospholipids during growth. However, the incorporation of n-3 fatty acids in pups was significantly suppressed whereas that of n-6 fatty acids was increased when 18:2n-6 was replaced by its delta 6-desaturation product, 18:3n-6 (concentrated from evening primrose oil), as the source of n-6 fatty acid.(ABSTRACT TRUNCATED AT 250 WORDS)
Huang
Y S
YS
Efamol Research Institute, Kentville, Nova Scotia, Canada.
Wainwright
P E
PE
Redden
P R
PR
Mills
D E
DE
Bulman-Fleming
B
B
Horrobin
D F
DF
D000818:Animals; D000833:Animals, Suckling; D004041:Dietary Fats / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005227:Fatty Acids / Q000032:analysis; D015525:Fatty Acids, Omega-3 / Q000494:pharmacology*; D043371:Fatty Acids, Omega-6; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology*; D005260:Female; D006321:Heart / Q000187:drug effects; D007668:Kidney / Q000737:chemistry / Q000187:drug effects; D007774:Lactation; D008099:Liver / Q000737:chemistry / Q000187:drug effects; D008297:Male; D051379:Mice; D009206:Myocardium / Q000737:chemistry; D010713:Phosphatidylcholines / Q000032:analysis; D010714:Phosphatidylethanolamines / Q000032:analysis; D010743:Phospholipids / Q000737:chemistry*
D004041:Dietary Fats; D005227:Fatty Acids; D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6; D005231:Fatty Acids, Unsaturated; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D010743:Phospholipids