Serotonin secretion

The selectivity of the SSRIs does not mean that they are totally without side effects. First, serotonin-secreting nerve cells are distributed throughout the brain and control a wide array of nervous system activities. As a result, increasing serotonin not only relieves depression, it can also produce many side effects such as abdominal discomfort, sexual dysfunction, and anxiety. Second, the selectivity of the SSRIs is not absolute but relative. Although the main action of the SSRIs is the same, they do have differences. For patients, this means that the drug interactions and side effects of the SSRIs vary somewhat. It also means that a patient who does not respond to one SSRI may respond to another. 

In addition to their functions as presynaptic autoreceptors, 0C2AR can also modulate release of other neurotransmitters (Figure 3). In the CNS, 0C2A and 0C2C receptors inhibit dopamine release in basal ganglia (Bucheler et al. 2002) as well as serotonin secretion in mouse hippocampus and brain cortex (Scheibner et al. 2001a). In the enteric nervous system, the release of acetylcholine as determined by [3H] -choline overflow from tissue slices was selectively inhibited by (X2aAR (Scheibner et al. 2002). 

As ccanpared with modified cholesterol ioimal platelets, the dose response curves for both aggregation and serotonin secretion in response to a-thrombin imderwent a leftward shift using cholesterol-enriched platelets and a rightward shift using cholesterol-depleted... 

PAF stimulates platelet aggregation and serotonin secretion in a stracturally specific maimer. For example, lyso-PAF, the inactive stmctural analog has no platelet activating... 

ShuUa SD, Hanahan DJ. AGEPC induced stimulation of rabbit platdets corrdation between PA levd, Ca uptake [H] serotonin secretion. Arch Biochem Biophys 1984 259 1468-1471... 

Osamura RY, Oberg K, Speel EJ, et al. Pancreatic endocrine tumours serotonin-secreting tumour. In Delellis RA, Lloyd RV, Heitz PU, Eng C, eds. WHO Classification of Tumours. Pathology and Genetics of Tumours of Endocrine Organs. Lyon, France lARC Press 2004 198. 

Drugs that block binding sites include selective serotonin reuptake inhibitors (SSRIs). In 1970, the Eli Lilly Company developed fluoxetine (Prozac). Their research began with nizoxetine, a selective norepinephrine reuptake inhibitor. Of the compounds that inhibited reuptake of serotonin, norepinephrine, and dopamine, fluoxetine was the most potent and selective inhibitor of serotonin reuptake. It was approved for use by the FDA in December, 1987, and used to reduce excessive serotonin secretion from carcinoid tumors. 

The unusual flavonoid derivative kuwanon G, 30, is reported to lower blood pressure in rabbits when administered intravenously at a dose of l.Omg/kg of body weight (743). (-h)-Catechin [(-h)-cyanidan-3)ff-ol], 31, is remarkably bioactive. Among its recently reported biological effects are the following antianaphylactic (517), anticoagulant (569), antihepatotoxic (963), platelet aggregation inhibition (118), and serotonin secretion inhibition (100) effects. 

Kanerva K, Lappalainen J, Makitie LT, Virolainen S, Kovanen PT, Andersson LC (2009) Expression of antizyme inhibitor 2 in mast cells and role of polyeunines as selective regulators of serotonin secretion. PLoS One 4 e6858... 

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