Depression Causes and Treatment Methods from a Neurobiological perspective

What does Depression mean?

Clinical Depression is commonly referred to MDD, Major Depressive Disorder

It´s a medical condition with many emotional, physical behavioural and cognitive symptoms

Sympthomes of Depression

• continuous low mood or sadness
• feeling hopeless and helpless
• having low self-esteem
• moving or speaking more slowly than usual
• changes in appetite or weight (usually decreased but sometimes increased)

Serotonin

Serotonin is a monoamine neurotransmitter

Important because of the serotonin hypothesis of depression

It is a contributor to feelings of well-being and happiness

Noradrenaline

Noradrenaline

Noradrenalin is an organic chemical which works in the synaptic cleft as a neurotransmitter

Noradrenaline neurons are enriched in the Locus coeruleus, a brainregion which controlls emotions

Noradrenaline Research

The Noradrenaline Hypothesis for Mood Diseases from the 1960 explains a correlation between the noradrenaline leve and a depression

The cerebral cortex of suicide victims have more noradrenaline receptors

Reboxetin, a antidepressant which cooperates with noradrenaline shows significant effects

Noradrenaline Research

Selective serotonin reuptake inhibitors (SSRIs)

• citalopram
• escitalopram
• fluoxetine
• fluvoxamine
• paroxetine
• sertraline

These types tend to have fewer side effects

Side effects:

dry mouth, nausea, headaches, nervousness, restlessness, trouble sleeping, sexual problems

SSRIs usually first kind of antidepressant a doctor will prescribe

Serotonin and norepinephrine reuptake inhibitors (SNRIs)

SNRIs affect two chemicals in your brain (serotonin and noradrenaline)

• duloxetine
• venlafaxine
• desvenlafaxine

Side effects:

nausea, nervousness, headaches, lack of energy, dry mouth, weight loss, sexual problems, increased heart rate

they don’t interact with your other medicines

Monamine oxidase inhibitors (MAOIs)

• isocarboxazid
• phenelzine
• selegiline
• tranylcypromine

Side effects:

weakness, dizziness, headaches, and trembling

MAOIs in combination with other medicine often causes the "Serotonin Syndrom"

MAOIs typically are used as a last resort, if other types haven’t worked

Experiment

mice, with different infusions

an acrylic glass cylinder filled with water

Experiment is divided in two trials where the mice are forced to swim

first trial last for 15 min

after 24-hours, a second trial is performed that lasts 6 min

Results

duration of time spent as “Immobile” if the mouse is floating with the absence of any movement

Code the duration of time spent as “Struggling/climbing”

Code the duration of time spent as “Swimming” movement of forelimbs or hind limbs in a paddling fashion

Conclusion

Immobility is interpreted as a signal of less motivation which leads to depression

The mouse with the SSRI Escitalopram was the shortest time immobil

From that it follows, that the antidepressant Escitalopram is more sufficient than herbal treatmants or saline