Condensation activity for polyunsaturated fatty acids with malonyl-CoA in rat brain microsomes. Characteristics and developmental change.
Condensation activities for gamma-linolenic acid (18:3(n-6)), octadecatetraenoic acid (18:4(n-3)) and eicosapentaenoic acid (20:5(n-3)) with malonyl-CoA were measured and compared with the condensation activities for 16:0-CoA, 18:1-CoA, 18:2(n-6)-CoA and 18:3(n-3)-CoA in rat brain microsomes of various ages. The age-dependence of condensation activities for 18:3(n-6), 18:4(n-3) and 20:5(n-3) showed a maximum at 1- to 2-month-old and were still higher at 3-month-old 2- to 3-fold than the activities in microsomes of pups. Conversely, the age-dependence of condensation activity for 16:0-CoA showed a peak around 1 month-old, but decreased at 3-month-old to the level of the activities in pups. The condensation activity for 20:5(n-3) was inhibited by 18:3(n-6) or 18:4(n-3) and the inhibition was not competitive. The condensation of 18:3(n-6) was also inhibited by 18:4(n-3) in the same manner. A physiological implication of the inhibition system at the substrate level was discussed.
Yoshida
S
S
INSERM U.26, Hôpital Fernand Widal, Paris, France.
Bourre
J M
JM
D000818:Animals; D001921:Brain / Q000254:growth & development / Q000378:metabolism*; D002855:Chromatography, Thin Layer; D005231:Fatty Acids, Unsaturated / Q000378:metabolism*; D008297:Male; D008316:Malonyl Coenzyme A / Q000378:metabolism*; D008861:Microsomes / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
D005231:Fatty Acids, Unsaturated; D008316:Malonyl Coenzyme A