Assimilation of ¹⁴C-Linoleic Acid by the Rat Fetus

Abstract

Following ingestion, by the 20-day pregnant mother, of (1-¹⁴C)linoleic acid, the retention and distribution of ‘⁴C are determined in the fetus, placenta and mother, after 1, 3 and 6 h. Comparison of the specific activities of linoleic and arachidonic acids in the maternal plasma, liver and placenta, and the fetal plasma, liver and carcass leads to the conclusion of a selective materno-fetal transfer of arachidonic acid, relative to linoleic acid, through the placenta.

Prenatal protein depletion and Δ9, Δ6 and Δ5 desaturases in the rat

“…Apparently, these sequences of metabolic events involved in the synthesis of arachidonic acid are limited by the in vivo activity of A6-desaturase, since the desaturation of linoleic to 71inolenic acid is a rate-limiting step in the conversion of linoleic to arachidonic acid (2). Following the ingestion of [ 1-14C] linoleic acid by pregnant rats, Pascaud et al (3,4) demonstrated that: 1) fetal arachidonic acid is originated essentially iW the maternal liver, and 2) this acid is selectively transferred from mother to fetus through the placenta.…”

Desaturation of ¹⁴C Linoleic Acid by the Rat Fetus

“…The importance of the maternal blood in the supply of w6 polyunsaturated fatty acids to the fetus [6], suggested by in vitro investi gations on the rat fetoplacental unit [9], has been demonstrated in our laboratory by in vivo isotopic experiments to be reported elsewhere.…”