Essential Fatty acids

• Omega 3 – if the first double bond is located 3 carbons from the omega end or methyl end then it is the omega 3. (some have positive effect on heart rhythm and can help in decreasing chances of blood clotting for MI)

  • Alpha linolenic acid – major omega -3 (from diet)

• Omega 6 – if the first double bond is located 6 carbons from the omega end

  • Linoleic acid – major omega 6 (from diet)

• Omega 9 – if the first double bond is located 9 carbons from the omega end

  • Oleic acid – major omega 9

• Eicosanoids  collectively they are referred to as local hormones (typically not carried to other sites and act locally) dietary factors can contribute to the effect or regulation of these hormones

  • Hormone – a chemical messenger

    • Prostaglandins – PG  involved in sleep reg., body temp, ovulation, endometrial lining produces many of these in the uterus (effect on uterus and muscles on head)

    • Prostacyclins – PGI  tend to inhibit TX and interfere with blood platelets

    • Thromboxanes – TX  effect on blood platelet function, can cause them to clot and release serotonin, which causes vasoconstriction

    • Lukotrienes – LT  more involved in causing contractions of smooth muscles in respiratory and GI contractions. Mainly in allergic reactions

    • Lipoxins – LX  same as LT

Aspirin  makes platelets less sticky

Category: Biochemistry Notes