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Adrenal Medulla Adrenaline Noradrenaline Dopamine And Enkephalin |
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An informative article on: Adrenal Medulla Adrenaline Noradrenaline Dopamine And Enkephalin. The adrenal glands are found just above the kidneys, and are referred to as “kidney hats”. Both of these adrenal glands are separated into two structures, the adrenal cortex and the adrenal medulla. The adrenal medulla secretes hormones such as adrenaline, noradrenaline and small amounts of dopamine directly into the blood in response to stress such as danger, mental stress or physical exercise. This is also known as the “fight-or-flight” response that many are familiar with. These also work with enkephalins to inhibit the transmission of pain signals to the brain and endocrine system. Adrenal Medulla Functions The adrenal medulla is the center of the adrenal gland, surrounded by the adrenal cortex, and receives input from the nervous system. It is primarily composed of hormone-producing chromaffin cells which convert the amino acid tyrosine into adrenaline, noradrenaline and dopamine. Adrenaline Adrenaline, also known as epinephrine, is secreted from the adrenal medulla, boosting the supply of oxygen and glucose to the brain. This increases heart rate and blood pressure, dilates pupils, constricts blood vessels in the skin and intestines, and decreases metabolism. Other common effects are goosebumps, also known as gooseflesh or goosepimples, causing the hairs on your arms to stand on end. Adrenaline is a breakdown product of noradrenaline. Noradrenaline Noradrenaline, also known as norepinephrine, comes from tyrosine, and is then broken down to form DOPA, which is broken down into dopamine. Approximately 15% of the noradrenaline produced is stored for later release. The remainder goes back to be broken down further into adrenaline. This will boost the supply of oxygen and glucose to the brain and muscles, and increase skeletal muscle readiness. This prepares your body to react to stressors. Dopamine Dopamine, also known as DA, comes from noradrenaline and causes your body to increase heart rate and blood pressure. It interacts with receptors on some nerve fibers and many neurons. Because it cannot go past the blood-brain barrier, given as a drug, it does not directly affect the central nervous system. Dopamine is not only a precursor of noradrenaline and adrenaline, but is also a neurotransmitter. It has many functions in the brain, including behavior and cognition, sexual gratification, mood, learning, sleep, memory, motivation, lactation, and involuntary movement. Enkephalin Enkephalin is the body’s natural painkiller. Whenever someone is injured, pain impulses will travel up the spinal cord to the brain, causing the brain to release endorphins and enkephalin. Enkephalin blocks the pain signals in the spinal cord. In the 1960s, doctors found that opiate narcotics such as opium, morphine and heroin mimic the actions that should naturally occur within the brain. Unfortunately these drugs are also highly addictive. In safe measures, together the adrenal medulla, adrenaline, noradrenaline, dopamine and enkephalin protect us by secreting the hormones needed to keep us safe under both mental and physical stress, increase pleasure, and block pain. In access, they will also suppress digestion and the immune system, and increase the chance of stroke, heart attack and ulcers. Contact your doctor if you feel that your automatic responses seem to be either overactive or sluggish, which could be a sign that any, or all, need help to become regulated. |