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What Happens When I Get Depressed?
ОглавлениеThe brain relays electrical messages from one nerve cell to the next with the aid of neurotransmitters. There exist around 40 of these substances whose role is to cover the space between the nerves (the synapses) so that the signals pass unimpeded.
Depression is thought by many doctors, nutritionists and researchers to be caused by a deficiency of neurotransmitters. Up until quite recently it was assumed that these vital substances occur in the brain and are not dependent on, or directly influenced by, the food we eat. The blood-brain barrier was always thought to insulate the brain from the effects of incorrect diet. We now know that neurotransmitters can be deficient, and that they can be influenced by nutritional supplements and dietary manipulation.
Examples of neurotransmitters include serotonin, dopamine, acetycholine, epinephine (adrenaline), glycine and GABA (gamma-aminobutyric acid) and the endorphins. Prescription drugs for depression influence these important chemicals.
ANTIDEPRESSANT DRUGS
The antidepressant drugs in common use fall into three separate drug groups. Each group has a different mode of action on the brain chemistry.
1 MONOAMINE OXIDASE (MAO) INHIBITORS These drugs inhibit the enzyme (MAO), that is responsible for the metabolic breakdown of the neurotransmitters, including serotonin, dopamine, epinephrine (adrenalin) and norepinephrine (noradrenaline). This allows for more of the neurotransmitters to be in circulation. The best known drugs in this group are Parnate, Nardil and Parstelin.
2 TRICYCLICS This group of drugs leads to reduction of histamine and an increase in noradrenaline. The most common of these drugs include Amitriptyline, Imipramine and Anafranil.
3 SELECTIVE SEROTONIN RE-UPTAKE INHIBITORS (SSRI’s) These work by selectively reducing the uptake of Serotonin, thus allowing more Serotonin into the circulation. The best known drug in this group is Prozac.
