Norepinephrine and dopamine are utilized in brain circuits which regulate all body functions, mood, emotions, and cognitive abilities. These transmitters are made from amino acids, supplied as proteins in foods or as free amino acids in formulas such as Alpha ENF. Phenylalanine and tyrosine are first converted to l-dopa, then dopamine, which can be converted to norepinephrine and epinephrine.

Norepinephrine is widely distributed in the brain and is the neurotransmitter in neurons that determine consciousness, sleep rhythms, attention, and vigilance. NE cell clusters within the brain's arousal complex (locus coeruleus) organize sleep patterns. In rats, painful, uncontrollable electrical shocks induce “depression” and are associated with early depletion of NE in the locus coeruleus.

Underproduction of NE may lead to depression. Some antidepressants, especially imipramine, selectively alter the synthesis of NE, but paradoxical experimental results tell us that therapeutic changes are not achieved by just increasing one transmitter but rather influencing the net arousal balance in the mesh of arousal circuits.

Imipramine, the grandmother of the family of tricyclic antidepressants, has at least a triple action on NE, acetylcholine, and histamine circuits. Imipramine's cousin, amitriptyline, works more on the serotonin neurons and also has marked anti-acetylcholine activity. Both drugs are also good antihistamines.

The substrates of NE, phenylalanine, tyrosine, and l-dopa are not powerful antidepressants, but they may have a contributing role in a well thought-out neurochemical recipe. Stimulants, including caffeine, cocaine and amphetamines act in a NE-increasing mode with temporary increase in psychic energy and a sense of well-being. They also influence the dopamine system.

Repeated use of these drugs leaves the over stimulated brain circuits in a state of confusion, with disturbances of psychic energy, thinking, feeling, and behaving. Withdrawal from these drugs is associated with other marked disturbances.

Amphetamines will induce agitated, paranoid, and violent states in susceptible people. As street drugs, amphetamines have major antisocial consequences. Antidepressants of the MAO-inhibitor group (parnate, nardil) increase norepinephrine levels but not serotonin.

Order Books: Click the green  button on the left  to order printed books from Alpha Online. Click the yellow download button on the right for eBook (PDF file) download at Persona Digital Online.

Human Brain in Health and Disease

Neuroscience Notes

You are viewing the Brain Mind Center at Alpha Online.  Persona Digital publishes Philosophy, Psychology and Neuroscience books. The topics discussed at the Brain Center are taken from this series of books. These books are available as print editions at Alpha Online or they can be downloaded from  Persona Digital  a separate online site where you can read book topics and download eBooks as PDF files.

You are at Alpha Online, a division of Environmed Research, founded in 1984 at Vancouver, BC, Canada. Online Since 1995. Alpha Nutrition is a trademark and a division of Environmed Research Inc. All Alpha Education books, eBooks and Starter packs are ordered online.  We are located at Sechelt on the Sunshine Coast, close to Vancouver, British Columbia, Canada.