Definition
Definition
Dopamine is a neurotransmitter (liquid allowing the patient to pass nerve impulses between neurons or nerve cells) belonging to the catecholamines of which there are three categories:
- The adrenalin.
- La norepinephrine.
- Dopamine.
Anatomy
The production of dopamine is carried out by a variety of neurons called dopaminergic, which can be found in:
- The hypothalamus (central area of the brain playing a role in regulating the body's functions (hunger, hot-cold, sexual activity, etc.).
- Le locus niger (area of the cerebral peduncle located in the midbrain or midbrain), located between the cerebrum and the spinal cordThis area is involved in the regulation of automatic movements.
- The striated bodies (clusters of gray matter embedded in white matter: central gray nuclei) located in the lower part of the two cerebral hemispheres (halves of the brain).
Between these different areas there are links called nigrostriatal tract.
Symptoms
physiology
Dopamine is the substance in the brain that plays a role in controlling movement.
It inhibits the action of the Prolactin.
Unlike everyone else catecholamines, dopamine has vasodilatory capacities (increase in the caliber of the vessels) at the level of the waist, intestine and coronary.
Pathophysiology
Diseases related to the absence or deficiency of dopamine in these nigrostriatal pathways:
Parkinson's disease is a neurological condition accompanied by:
- Tremor.
- Decreased movement.
- D’hypertonia (rigidity in movements that appear jerky).
- Slow, regular tremors, affecting mainly the hands and feet (exaggerated by emotions, and disappearing during voluntary movements and during sleep).
Parkinson's syndrome caused by the use of neuroleptiques (drugs that exert a sedative action on the nervous system, they are also called neuroplegics, and are used in the treatment of psychoses (mental illness that the subject does not recognize and does not accept, unlike the neurosis), characterized by the loss of contact with reality accompanied by a more or less serious alteration of the personality.
Medical exam
Labo
L'inhibitors factor, also called IH is an inhibitory hormone from the hypothalamus.
For example the PIF is the factor inhibiting the secretion of Prolactin.
Technical
Serum dopamine levels :
- 50-580 picomolles per liter or 10-110 picograms per milliliter.
- maximum: 2900 nanomoles per 24 hours or 550 µg per 24 hours
Urine dosage :
- picomolles per liter X 0,189 = picograms per milliliter.
- picograms per milliliter X by 5,27 = picomolles per liter.
Treatment
Treatment
Dopamine is used therapeutically for:
- Increase the contraction force of the the heart.
- A decrease in the amount of dopamine in the circulating blood.
- In an emergency when there is a state of cardiogenic shock.
- If you have a trauma important.
- After a one infection.
Contraindications :
- Pregnancy et feeding.
- Allergy.
- Pheochromocytoma (tumor of the glands adrenal located above the two kidneys) which can cause a significant increase in blood pressure.
.
Evolution
Side effects
Its use is in the context of cardiological resuscitation, it is likely to cause side effects:
- Nausea.
- vomiting.
- Crises ofangina (angina pectoris due to closure of the coronary arteries supplying the heart muscle - myocardium -).
- Heart rhythm disturbances.