Signal serotonin

Neurotransmitters are molecules that convey a signal from one nerve cell to the other. Neurotransmitters can be biogenic amines (e.g. norepinephrine, serotonin),... 

HT3 receptor. 5-Hydroxytryptamine receptor a receptor for serotonin (a neurotransmitter), which activates a variety of second messenger signaling systems and through them indirectly regulates the function of ion channels. 

Saudou, F., Boschert, U Amlaiky, N Plassat, J. L and Hen, R. (1992). A family of Drosophila serotonin receptors with distinct intracellular signalling properties and expression patterns. EMBO J. 11 7-17. 

Figure 3.2 Normally, when the stomach is full it sends a signal to the brain telling the body to stop eating. This message is carried by neurotransmitters (chemical messengers in the brain) to the hunger center in the hypothalamus (a part of the brain). Examples of neurotransmitters that carry this message are norepinephrine, serotonin, and dopamine. Many diet pills increase these same neurotransmitters that signal the brain that the stomach is full. These diet pills, called appetite suppressants, trick the brain into thinking the stomach is full and therefore decrease hunger.

The profound effects of Li+ upon phosphoinositide metabolism and cell signaling have been the subject of several recent reviews [54,81,85,86]. These effects are dependent upon receptor stimulation of the phosphoinositide cycle by a range of stimuli, including norepinephrine, serotonin, and carbachol the basal turnover of this cycle is largely unaffected by Li+ [82,87,88]. 

This transmembrane signaling system involves a complex consisting of several functional proteins (Figure 7) stimulatory (e.g. P-adrenergic, dopamine Dp serotonin, vasopressin) [124] and inhibitory (e.g. a2-adrenergic, dopamine D2, opiod, and muscarinic) [125] receptors, stimulatory (Gs) and inhibitory (G ) G-proteins, and the catalytic protein, adenylate cyclase. On stimulation of a receptor, an associated G-protein binds GTP and the resulting receptor/G-protein/GTP complex then activates, or inhibits, adenylate cyclase in the catalysis of the synthesis... 

Da Prada, M. and Kellermann, O. (2006) Serotonin transport and serotonin transporter-mediated antidepressant recognition are controlled by 5-HT2B receptor signaling in serotonergic neuronal cells. FASEB Journal, 20 (11), 1843-1854. 

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