Histamines are tiny crystals in the body made from the amino acid Histidine when it decarboxylases. Histamine occurs naturally in just about every living animal. Histamine is histamine and can have the same effect on you whether your own body makes it or you eat a food that is rich in it. Histamines that occur naturally in your body are stored in specialized cells called mast cells and basophils. Eating spoiled fish can cause a severe allergic reaction because the bacteria in the fish stimulate the H2 receptors in the Gastric Parietal cells and release all sorts of histamine havoc on your system.
Histamines are most often associated with the runny nose and watery eyes that you get from a cold or hay fever but they do a lot more than that.
Histamines also affect:
- · Digestion
- · Breathing
- · Mood
- · Sleep
- · Inflammation
- · The Allergic Response
- · Smooth muscle contraction
- · Vasodilation -(Dilation or widening of the blood vessels)
- · Edema-(Swelling caused by fluid in your body tissues)
- · Vascular Permeability-(The ability of molecules to pass through blood vessels)
How It Works:
When something like a virus, bacteria or other substance that your body perceives to be a threat invades, it causes a chain reaction. First, it stimulates tiny particles on mast cell and basophil membranes called Histamine Receptors. These Histamine Receptors then send signals to the mast cells and basophils where the histamine is being stored telling them to release the histamine. Once the histamine is released, it causes other nearby cells to lose permeability and allow fluid to escape. This causes the area to become engorged and inflammation occurs when fluid becomes trapped and the area between surrounding tissue becomes swollen. Antibodies in your blood, which ideally kills the foreign invader, flock to the site and become trapped in the inflamed tissue.
Sometimes, for a variety of different reasons, these Histamine Receptors send false alarms to the mast cells and basophils and like a prankster dialing 911, the histamine cops show up acting like they are at an Occupy Wall Street protest or something and start arresting cells without any probable cause. This is why people sometimes get the hives and/or more serious allergic reactions to medications, foods and otherwise harmless substances.
There are four different types of Histamine Receptors, each controlling a slightly different function in the body:
- H1-Found in smooth muscle cells: Triggers the acute allergic response
- H2-Found in Gastric Parietal Cells in the stomach: Responsible for secretion of gastric acids
- H3-Found in the Central Nervous System: Modulates neurotransmission
- H4-Found in Mast Cells, Eosinophils, T Cells, Dentric Cells: Regulates Immune Response
Most primitive Antihistamines work on the Histamine Receptors to keep them from becoming stimulated and therefore the cell does not release the Histamines into the nearby tissues. Perhaps the most common of these is Diphenhydramine, the active ingredient in Benadryl. Although Diphenhydramine is still widely used, especially in an emergency when an allergic reaction occurs, pharmaceutical companies are working to create more targeted antihistamines with less side effects. The most common side effect of Diphenhydramine is sleepiness.
People with higher than average levels of histamines are often hyperactive and studies suggest that they are more prone to commit suicide when they have suicidal ideations. Lower than average amounts of histamine have been shown to cause depression and sleepiness. Histamine deficiencies have also been associated with MS (Multiple Sclerosis).
Histamines stimulate the production of digestive enzymes and gastric acids which aid in protein digestion. Histamine Deficiency can cause the body to become more dependent on carbohydrates which can lead to higher cholesterol levels. Excess histamines in the blood can cause Anaphylaxis (a severe reduction in the blood flow along with smooth muscle contractions in the trachea) which can lead to suffocation and render the heart incapable of keeping up with the body’s demand for blood. Too many Antihistamines can cause Anaphylaxia.
Histamine crystals dissolve easily in water and melt at 840C (183.20F).
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