Pineal glands were analysed for 5-HT
and 5-hydroxyl-indole3-acetic acid (5-H1AA) contents using HPLC with electrochemical detection.
Increased plasma levels of free TRP favor increases TRP concentrations in the central nervous system (CNS), and thus any condition that increases this amino acid in the plasma will induce increased concentrations in the CNS and hence the central biosynthesis of 5-HT
sup] The precise mechanism accounting for the association remains unknown, but an important role of 5-HT
has been proposed: excessive 5-HT
in depression may increase platelet activity and trigger platelet aggregation, which may trigger the plaque formation associated with CHD.
TRP accessibility to the brain also shows an important role in central 5-HT
synthesis because tryptophan hydroxylase, the rate limiting enzyme of the serotonin biosynthetic pathway, is unsaturated with its substrate (TRP).
The reinforcing effects of MA on behavior are mainly mediated through dopamine (DA) and 5-hydroxytryptamine (5-HT
) neurotransmission in the brain and primarily depend on its ability to increase DA and 5-HT
release in the terminal regions of the mesoaccumbens and neostriatum.
Tryptophan depletion was reported to impaired memory processes by affecting brain TRP levels, thereby decreasing 5-HT
For half a century, our field tenaciously held to the monoamine theory, which posits that depression is caused by a deficiency of 5-HT
or NE, or both.
He covers 5-HT
systems and neurobiological marks related to memory systems; 5-HT
pathways, receptors, and transporter: memory functions and dysfunctions; and nine specific 5-HT
receptors, including 5-HT
6 and its related neural markers and memory tasks.
Successful injection of 5-HT
was verified via coadministration of India ink (1 pi, proper distribution of the ink in the cerebroventricular system) with 5-HT
, and data from animals with unsuccessful injection were excluded.
In contrast to buspirone, paroxetine is a potent and selective inhibitor of the 5-HT
transporter (Nemeroff and Owens, 2003).
diomedea is the only species in which TPep has been shown to cause ciliary locomotion, while 5-HT
causes ciliary beating in many gastropods.
A decrease in the content of central 5-HT
is a risk factor for PE.