Sarda N, Gharib A, Croset M, Molière P, Lagarde M
INSERM U 205, INSA de Lyon, Villeurbanne, France.
Biochim Biophys Acta. 1991 Jan 4;1081(1):75-8. doi: 10.1016/0005-2760(91)90252-d.
When compared to brain, the fatty acid composition of the rat pineal gland revealed that the total proportion of n-6 polyunsaturated fatty acids (PUFA) was 2.3-fold higher, whereas the proportion of n-3 fatty acids was similar. Specifically, 20:4(n-6) and 18:2(n-6) were respectively 1.56- and 11.80-fold higher in the pineal than in the brain, while the proportions of 22:6(n-3) were similar in both tissues. In addition, 18:1(n-9) was found 2.15-fold lower in the pineal. Feeding adult rats with fish oil concentrates induced a significant alteration of the polyunsaturated fatty acid composition of the pineal. There was a reciprocal replacement of the n-6 by the n-3 fatty acids. Conversely, in rats fed a n-3 fatty acid-deficient diet (sunflower oil or coconut oil diet), the pineal gland contained reduced proportions of n-3 fatty acids. We conclude that the pineal gland (i) differs from the brain in containing much higher proportions of 18:2(n-6) and from the other tissues for its high proportions of 22:6(n-3) and (ii) is highly sensitive to the n-3 fatty acid diet in contrast to what is known for the brain. These findings are discussed in the context of melatonin biosynthesis, the major hormone of the pineal gland.
与大脑相比，大鼠松果体的脂肪酸组成显示，n-6多不饱和脂肪酸（PUFA）的总比例高2.3倍，而n-3脂肪酸的比例相似。具体而言，松果体中的20:4(n-6)和18:2(n-6)分别比大脑高1.56倍和11.80倍，而两种组织中22:6(n-3)的比例相似。此外，发现松果体中的18:1(n-9)低2.15倍。用鱼油浓缩物喂养成年大鼠会导致松果体多不饱和脂肪酸组成发生显著变化。n-6脂肪酸与n-3脂肪酸相互替代。相反，在喂食n-3脂肪酸缺乏饮食（向日葵油或椰子油饮食）的大鼠中，松果体中n-3脂肪酸的比例降低。我们得出结论，松果体（i）与大脑不同，含有更高比例 的18:2(n-6)，与其他组织不同，含有高比例的22:6(n-3)；（ii）与大脑不同，对n-3脂肪酸饮食高度敏感。这些发现将在松果体的主要激素褪黑素生物合成的背景下进行讨论。
