A Possible Essential Role for Dietary Linolenic Acid in the Development of the Young Rat

Abstract

Female rats were fed semi-purified diets containing 10% safflower oil or 10% soybean oil for six weeks prior to mating and through-out pregnancy and lactation. The progeny were weaned to the diet of the dam. Physical, neuromotor and reflex development was monitored in the progeny prior to weaning and learning ability of the mature progeny was assessed in a simple Y-maze test. Brain lipid analyses were conducted in the progeny at birth, 21 and 210 days of age. Inclusion of soybean oil in the diet resulted in higher levels of 22:6omega3 and lower levels of 22:5omega6 in the brain ethanolamine glycerophosphatides. The nature of the dietary fat exerted no effect on the physical development, onset of reflexologic responses or onset of neuromotor co-ordination in the pups. The soybean oil-fed animals spent more time in certain neuromotor activities possibly associated with explorative drive than did their safflower oil-fed counterparts. The performance of the mature soybean oil-fed progeny in the discrimination-learning test was superior to that of progeny fed safflower oil. The association of superior learning capacity with dietary soybean oil-induced incorporation of omega3 fatty acids into the brain glycerophosphatides is offered as support for an essential role for dietary linolenic acid for the young rat.

The influence of an essential fatty acid deficient-diet on the reproductive performance of female rats

“…On the other hand, the addition of linoleic acid or its metabolic products, such as arachidonic acid or prostaglandin E 2 , to the EFAD diet have been shown to prevent impairment of the reproductive function (Burr and Burr, 1930 ;AlfinSlater et al, 1965 ;Tinoco et al, 1971 ;Hafiez, 1974 (Turpeinen, 1938 ;Panos and Finerty, 1953 Rivers, 1978 ;Rivers and Frankel, 1981 ;Tinoco, 1982) and, to our knowledge, there is no bibliographical evidence suggesting that n-3 fatty acids are required to maintain a normal pattern of estrous cycles. However, changes in other physiological functions have been observed in animals selectively deprived of n-3 fatty acids for prolonged periods (Castell et al, 1972 ;Benolken, Anderson and Wheeler, 1973 ;Lamptey and Walker, 1976 (Alling et al, 1972). In contrast with other authors (Evans, Lepkovsky and Murphy, 1934 ;Kummerow, Pan and Hickman, 1952), we found that sterility and maternal mortality during parturition were not significantly different among the three groups.…”

Mechanisms of action of docosahexaenoic acid in the nervous system

“…Representative studies in the animal literature (28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42) concerning the n-3 fatty acid deficiency syndrome are presented in Table 2. Only studies that focus on neural functions, notably brain and retinal functions, have been included here.…”

Polyunsaturated fatty acids, hyperlipidemia, and thrombosis.

“…24 For example, docosahexanoic acid (C22:6 co-3) appears to play a role in the proper functioning of nervous tissues, 25 and impaired maze-running abilities have been found in co-3 fatty-acid-deficient rats. 26 Remarkably high levels of C22:6 co-3 are found in brain and retinal cells as well as in spermatozoa. 24 Although further studies will be required to document structural or metabolic defects resulting from dietary co-3 fatty acid deprivation, the presence of high levels of these unique acids in certain tissues and the known Inability of mammalian cells to synthesize these de novo imply a dietary requirement for co-3 fatty acids.…”