Histidine is called a semi-essential amino acid (protein building block) because adults generally produce adequate amounts but children may not. Histidine is also a precursor of histamine, a compound released by immune system cells during an allergic reaction.
Histidine is an essential amino acid that is significant in the growth and repair of tissues. Histamine, an important immune system chemical, is derived from histidine. Histamine aids in sexual arousal. Because the availability of histidine influences histamine production, taking supplemental histidine-together with vitamins B3 (niacin) and B6 (pyridoxine), which are required for the transformation from histidine to histamine may help improve sexual functioning and pleasure.
Histidine is one of the basic (with reference to pH) amino acids due to its aromatic nitrogen-heterocyclic imidazole side chain. This amino acid is biochemically metabolized into the neurotransmitter histamine and the set of genes that produce the enzymes responsible for histidine biosynthesis are controlled by the well-studied histidine operon. The disruption of histidine biosynthesis in bacteria is the basis for the famous Ames test, used to determine the mutagenability of various chemicals. Histidine is incorporated into proteins and enzymes at a molar percentage of 2.1 compared to the other amino acids.
Uses and Benefits of Histidine
- Histidine is important for the maintenance of the myelin sheaths, which protect nerve cells, and is needed for the production of both red and white blood cells.
- In the lungs histamine causes bronchoconstriction to a slight extent in normal person but markedly in asthmatic patients.
- Histidine also protects the body from radiation damage, helps lower blood pressure, aids in removing heavy metals from the system, and may help in the prevention of AIDS.
- Histamine acts directly on the cardiac pacemaker and this causes increase in heart rate. Increase in heart rate also occurs due to reflex response of hypotension.
- In the gastrointestinal tract histamine causes intense stimulation of gastric hydrochloric acid secretion through H2 receptors
- Because histamine also stimulates the secretion of gastric juices, histidine may be helpful for people with indigestion resulting from a lack of stomach acid.
Rich Food Sources of Histidine
- Natural sources of histidine include rice, green vegetables,bananas, wheat, and rye.
- Animal sources: Meat, poultry, eggs, fish, dairy products like milk, cheese etc
Deficiency Symptoms of Histidine
- None known, but it is reported that histidine can cause pain in the bony joints.
- Inadequate levels of histidine may contribute to rheumatoid arthritis and may be associated with nerve deafness.
- Methionine has the ability to lower histidine levels.
- Lysine : The essential amino acid that is a basic building block of all protein. (blissreturned.wordpress.com)
- Threonine : The essential amino acid that helps to maintain the proper protein balance in the body. (blissreturned.wordpress.com)
- Tryptophan: The essential amino acid that is needed to maintain optimum health. (blissreturned.wordpress.com)
- Methionine : The essential amino acid which assists with metabolic function, breaks down fat, and is the primary source of sulfur in the body. (blissreturned.wordpress.com)