Adrenaline



Definition

Adrenaline is a hormone of the catecholamine family secreted by the adrenal glands and the central nervous system.

This neurotransmitter is biosynthesised by the central nervous system from tyrosine, which leads successively to dopamine, noradrenaline and adrenaline.

It is then released into the blood and binds to cells equipped with beta receptors located in a large number of organs (heart, pancreas, kidneys, intestines, skin, arteries, etc.).

With the chemical formula C9H11NO3, adrenaline can also be chemically synthesised for medical use, in which case it is called epinephrine.

The role of adrenaline

Nicknamed the 'stress hormone', adrenaline is released during intense emotional states (stress, fear, anger) or during significant physical activity.

It responds to an increased need for energy to face danger, to resist pain or to cope with lack of oxygen.

It also regulates blood glucose by accelerating the conversion of glycogen into glucose and its availability in the blood.

Finally, it increases thermogenesis by accelerating the production of heat by brown adipose tissue.

Effects of adrenaline

  • Tachycardia and palpitations
  • Bronchial and pupil dilation
  • increased blood pressure
  • tremors
  • Cessation of intestinal contractions
  • Narrowing of the skin arteries (paleness, sweating, raised hairs)

Adrenaline production

Too much stress depletes the body's adrenaline reserves.

To prevent the body from running out of adrenaline, a diet rich in phenylalanine and tyrosine is essential in times of stress, as these two amino acids form the basis of adrenaline production.

The synthesis of catecholamines is therefore a cascade reaction between the two amino acids phenylalanine and tyrosine.

Tyrosine is hydroxylated to DOPA by an enzyme called tyrosine 3-hydroxylase.

DOPA is then decarboxylated to dopamine by a specific aromatic amino acid decarboxylase using a cofactor, pyridoxal phosphate, the active form of vitamin B6.

It can be hydroxylated to norepinephrine by dopamine beta-hydroxylase, whose cofactors are vitamin C and copper.

This in turn is methylated to adrenaline by phenylethanolamine N-methyltransferase (PNMT), an enzyme that uses S-adenosyl-methionine (SAM) and cortisone as cofactors.

To synthesise adrenaline, you need to eat foods rich in phenylalaninetyrosinevitamin B6vitamin C, and copper.

Food source

Phenylalanine and tyrosine

  • Meat: turkey, duck, chicken, pork
  • Wheat germ
  • Oat Flakes
  • Cereal
  • Poached eggs
  • Hazelnuts
  • Bean sprouts
  • Yoghurt

Vitamin B6

  • Liver
  • Herring
  • Salmon
  • Walnut
  • Peanut
  • Wheat Germ
  • Brown Rice
  • Yeast

Vitamin C

  • Berries and red fruits: strawberries, currants, blueberries...
  • Sweet peppers
  • Cabbage
  • Citrus fruits
  • Kiwi
  • Chives

Copper

  • Offal
  • Oysters
  • Chocolate
  • Cuttlefish
  • Walnuts & Hazelnuts
  • Sunflower Seeds