The discovery of norepinephrine uptake in sympathetic nerves by Julius Axelrod and colleagues in the 1960's is an example of how a new scientific discovery can have a profound impact on the development of new therapies. The understanding that antidepressants acted as inhibitors of monoamine reuptake led to the development of many new drugs of this type. The older tricyclic antidepressants suffered from serious toxicology due to secondary pharmacological effects, notably on the heart They were followed by the much safer serotonin selective reuptake inhibitors (SSRIs) (e.g. fluoxetine - "Prozac"), and subsequently by a new generation of mixed norepinephrine/serotonin reuptake inhibitors with improved safety profiles.
In addition monoamine uptake inhibitors are used in the treatment of obesity (sibutramine); smoking cessation (bupropion); and attention deficit hyperactivity disorder (ADHD) (atomoxetine). The amphetamines exert their psychostimulant effects by acting as selective ligands for norepinephrine and dopamine uptake, subsequently displacing dopamine and norepinephrine. Amphetamine and the analog methyl phenidate ("Ritalin") are widely used in the treatment of ADHD. The psychostimulant drug cocaine also acts by virtue of its ability to inhibit the dopamine transporter.
Finally, the selective neurotoxin 6-hydroxydopamine - whose use in brain was pioneered by Norman Uretsky - also acts by virtue of its recognition and uptake into monaminergic neurons by the norepinephrine and dopamine transporters.
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University of Oxford, UK
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Attention Deficit Disorder or ADD is a very complicated, and time and again misinterpreted, disorder. Its beginning is physiological, but it can have a multitude of consequences that come alongside with it. That apart, what is the differentiation between ADHD and ADD ADHD is the abbreviated form of Attention Deficit Hyperactive Disorder, its major indications being noticeable hyperactivity and impulsivity.