Restriction of maternal food intake inhibits fatty acid activation in developing rat hearts.

We studied the effect of restricting the diet of pregnant and lactating rats on the beta-oxidation of fatty acids by the developing heart in suckling pups. Control pregnant rats were fed a stock diet ad libitum. For the experimental group, food was restricted to half of the control intake on the seventh day of pregnancy and continued through lactation.

Differences in the fatty acid profile and beta-oxidation by heart homogenates of rats fed cis and trans octadecenoic acids.

Female Wistar rats were fed a fat-free diet containing either 5% partially hydrogenated corn oil (52.2% elaidate) or 5% oleic acid (67% oleate) with 8.6% linoleate providing 1% of calories 2 weeks before mating and were maintained on this diet throughout pregnancy and lactation.

Trans fatty acids: transport and positional specificity in rat placental lecithin.

Differences in positional incorporation of trans and cis isomers of octadecenoic and octadecadienoic acids in placental lecithin of rats was demonstrated. A 14C-labeled albumin complex of elaidic, oleic, linoelaidic, or linoleic acid was injected into the jugular vein of pregnant rats. 6 h later 45-64% of the total radioactivity in placental lipids was found in phospholipids (PL), with a major portion of the label incorporated into choline phosphoglycerides (CPC).

Effect of essential fatty acid deficiency on maternal, placental, and fetal rat tissues.

Prolonged dietary deprivation is needed to produce essential fatty acid (EFA) deficiency. But lack of EFA also impairs reproductive function. Inclusion of small amounts of linoleic acid in the diet can overcome this difficulty; further, if large amounts of oleic acid are included in the diet, this competes with the utilization of 18:2 producing EFA deficiency.

Positional specificity of trans fatty acids in fetal lecithin.

Differences in the positional incorporation of 9-trans[1-(14)C] octadecenoic (elaidic) and 9-trans,12-trans[1-(14)C] octadecadienoic (linoelaidic) acids in fetal lecithin of rats were demonstrated. On the 20th day of gestation, a 14C-labeled albumin complex of elaidic or linoelaidic acid was injected into the jugular vein of pregnant rats. For comparative purposes, 9-cis[1-(14)C] octadecenoic (oleic) or 9-cis,12-cis[1-(14)C] octadecadienoic (linoleic acid) was injected into the maternal circulation of rats.

Lack of catabolism of brain cholesterol.

Since direct intracranial injections of precursors indicate that cholesterol is synthesized in the brain at all ages, there must be a mode of disposal also. The sterol nucleus itself is not degraded by mammalian systems but the side chain can be metabolized. [26-14C] cholesterol was therefore injected directly into the brain of 8- to 19-day-old rats which were sacrificed at the end of 24 hr, 1 week and 2 weeks after injection.

Thyroid control over biomembranes: VI. Lipids in liver mitochondria and microsomes of hypothyroid rats.

The lipids of liver mitochondria prepared from normal rats and from rats made hypothyroid by thyroidectomy and injection with 131 INa contained similar amounts, per mg protein, of total lipids, phospholipids, neutral lipids and lipid phosphorus. Hypothyroidism caused a doubling of the relative amounts of mitochondrial cardiolipins (CL; to 20.5% of the phospholipid P) and an accompanying trend (although statistically not significant) toward decreased amounts of both phosphatidylcholines (PC) and phosphatidylserines (PS), with phosphatidylethanolamines (PE) remaining unchanged.

Placental transport of trans fatty acids in the rat.

Placental transport of 9-trans [1-14C] octadecenoic (elaidic) and 9-trans,12-trans [1-14C] octadecadienoic (linoelaidic) acids was demonstrated in rats. On the 18th day of gestation, a 14C-labeled albumin complex of elaidic or linoelaidic acid was injected into the jugular vein of pregnant rats. For comparison, 9-cis [1-14C] octadecenoic (oleic) or 9-cis,12-cis [1-14C] octadecadienoic (linoleic) acid also was injected into the maternal circulation of rats.

Trans fatty acids: positional specificity in brain lecithin.

Fifteen-day-old rats were divided into three groups: one group received an intracerebral injection of 5 microCi of 9-trans,12-trans [1-(14)C] octadecadienoic acid; the second group was given 5 microCi of the same compound plus an equal wt of nonradioactive all cis arachidonic acid; the third group was given 5 microCi of 9-trans [1-(14)C] octadecenoic acid. All animals were sacrificed 8 hr after injection. Glycerophosphocholine (GPC) was isolated and partically deacylated with phospholipase A2 from Crotalus Adamanteus venom.

Lipogenesis in the developing brain: utilization of radioactive leucine, isoleucine, octanoic acid and beta-hydroxybutyric acid.

Incorporation of radioactivity from intracranially injected radioactive leucine, isoleucine (ketogenic amino acids), octanoic acid and beta-hydroxybutyric acid into the brain lipids of 15 to 16 day-old rats was examined. The results showed that radioactivity from all the above precursors was incorporated into brain lipids. Radioactivity from injected isoleucine was incorporated into odd numbered fatty acids indicating an alternate pathway to alpha-oxidation for the biosynthesis of these fatty acids in the brain.

Biosynthesis of polyunsaturated fatty acids in the developing brain: I. Metabolic transformations of intracranially administered 1-14C linolenic acid.

Thirteen-day old rats were given intracranial injections of 1-14C linolenic acid (all cis 9, 12, 15 octadecatrienoic acid) and were sacrificed after 8 hr. Analysis of brain fatty acids showed that 16:0, 18:0, 18:1, 18:3, 20:3, 20:4, 20:5, 22:5, and 22:6 were labeled. The total fatty acid methyl esters were separated into classes according to degree of unsaturation on a AgNO3:SiO2 impregnated plate.

Metabolism of 1-(14)C linolenic acid in developing brain: II. Incorporation of radioactivity from 1-(14)C linolenate into brain lipids.

Metabolism of 1-(14)C linolenic acid was studied in growing animals by injecting the tracer intraperitoneally into 12-13 day old suckling rats and following up the results by sacrificing groups of animals at 8 hr, 48 hr, 15 day, and 45 day intervals. In the first 15 days, there was a greater decrease in radioactivity of brain total lipids compared to the later period, although the earlier age period is characterized by lipid deposition rather than breakdown. Since the 18∶3 ω3 family of fatty acids occurs largely in the brain total phosphatidyl ethanolamine fraction, we expected that, in the initial period, total phosphatidyl ethanolamine would be the most highly radioactive component.

Metabolism of linolenic acid in developing brain: I. Incorporation of radioactivity from 1-(14)C linolenic acid into brain fatty acids.

Twelve-thirteen day old rats were given 1-(14)C linolenic acid by intraperitoneal injection. Fatty acids were isolated from the brains of animals sacrificed at the end of 8 and 48 hr and 15 and 45 days. Eight hr after the tracer, radioactivity was found neither in 18∶3 nor its endproduct, 22∶6, and palmitate was the most highly radioactive component.