5-hydroxytryptamine binding

Pedigo NW, Yamamura HI, Nelson DL. Discrimination of multiple [3H]5-hydroxytryptamine binding sites by the neuroleptic spiperone in rat brain. J Neu-... 

Todd, R. D., and Bauer, P. A., 1988, Ascorbic acid modulates 5-[ H]-hydroxytryptamine binding to central 5-HT sites in bovine frontal cortex, J. Neurochem. 50 1505-1512. 

Important products derived from amino acids include heme, purines, pyrimidines, hormones, neurotransmitters, and biologically active peptides. In addition, many proteins contain amino acids that have been modified for a specific function such as binding calcium or as intermediates that serve to stabilize proteins—generally structural proteins—by subsequent covalent cross-hnk-ing. The amino acid residues in those proteins serve as precursors for these modified residues. Small peptides or peptide-like molecules not synthesized on ribosomes fulfill specific functions in cells. Histamine plays a central role in many allergic reactions. Neurotransmitters derived from amino acids include y-aminobutyrate, 5-hydroxytryptamine (serotonin), dopamine, norepinephrine, and epinephrine. Many drugs used to treat neurologic and psychiatric conditions affect the metabolism of these neurotransmitters. 

Peroutka, S.J., and Snyder, S.H. Multiple serotonin receptors Differential binding of [ H]5-hydroxytryptamine, [ HJlysergic acid diethylamide and [ H]spiroperidol. Mol Pharmacol 16 687-699, 1979. 

Roth, B. L., Craigo, S. C., Choudhary, M. S. etal. (1994). Binding of typical and atypical antipsychotic agents to 5-hydroxytryptamine- 6 and 5-hydroxytryptamine-7 receptors. /. Pharmacol. Exp. Ther., 268, 1403-10. 

Peroutka, S. and Snyder, S. H. Multiple serotonin receptors. Differential binding of [3H]-5-hydroxytryptamine, [3H] lysergic acid diethylamide and [3H]-spiroperidol. Mol. Pharmacol. 16 687-699,1979. 

Serotonin Binds to 5-hydroxytryptamine (5-HT) receptor to act as excitatory and inhibitory neurotransmitter in its inhibitory function, it can treat anxiety and depression in its excitatory function, it is an antipsychotic. 

Binds to DNA and prevents separation of the helical strands Affects neuronal transmissions Binds to opiate receptors and blocks pain pathway Acts as central nervous system depressant Inhibits Na/K/ATPase, increases intracellular calcium, and increases ventricular contractibility Blocks the actions of histamine on Hi receptor Blocks ai-adrenergic receptor, resulting in decreased blood pressure Inhibits reuptake of 5-hydroxytryptamine (serotonin) into central nervous system neurons Inhibits cyclooxygenase, inhibition of inflammatory mediators Inhibits replication of viruses or tumor cells Inhibits HIV reverse transcriptase and DNA polymerase Antagonizes histamine effects... 

Ramirez-Latorre J, Yu CR, Qu X, Perin F, Karhn A, Role L (1996) Functional contributions of alpha5 subunit to neuronal acetylchohne receptor channels. Nature 380 347-351 Rasmussen BA, Perry DC (2006) An autoradiographic analysis of [ l]alpha-bungarotoxin binding in rat brain after chronic nicotine exposure. Neurosci Lett 404 9-14 Reuben M, Clarke PB (2000) Nicotine-evoked [ H]5-hydroxytryptamine release from rat striatal synaptosomes. Neuropharmacology 39 290-299... 

Figure 17.37 Hay fever. Pollen grains bind to sensib sed mast cells which degranulate, releasing the active biochemicals that result in the allergic response. Serotonin is 5-hydroxytryptamine.

The main effects of BZs occur via positive allosteric modulation. The BZs and GABA bind to separate sites on the GABAa receptor complex. When a BZ occupies the BZ receptor, GABA s ability to open the chloride channels increases. With greater opening of the chloride channel, cellular excitability decreases (Ballenger, 1995). The final result of this decreased cellular excitability is widespread because of the extensive inhibitory role of GABA in the CNS. As a result, BZs may alter the turnover of neurotransmitters such as norepinephrine and serotonin (5-hydroxytryptamine [5-HT]). 

Whitehouse PJ, Price DL, Clark AW, et al Alzheimer disease evidence for selective loss of cholinergic neurons in the nucleus basahs. Ann Neurol 10 122-126, 1981 Whitehouse PJ, Price DL, Struble RG, et al Alzheimer s disease and senile dementia—loss of neurons in the basal forebrain. Science 215 1237-1239, 1982 Whitehouse PJ, Hedreen JC, White CL, et al Basal forebrain neurons in dementia of Parkinson s disease. Ann Neurol 13 243-248, 1983 Whitehouse P, Martino A, Antuono P, et al Nicotinic acetylcholine binding sites in Alzheimer s disease. Brain Res 371 146-151, 1986 Whitehouse PJ, Martino AM, Marcus KA, et al Reductions in acetylcholine and nicotine binding in several degenerative diseases. Arch Neurol 45 722-724, 1988 Whitton PS, Sama GS, O Connell MT The effect of the novel antidepressant tianeptine on the concentration of 5-hydroxytryptamine in rat hippocampal diasylates in vivo. Neuropharmacology 39 1-4, 1991 Whitworth P, Kendall DA Lithium selectively inhibits muscarinic receptor-stimulated inositol tetrakisphosphate accumulation in mouse cerebral cortex slices. J Neurochem 51 258-265, 1988... 

EGb inhibits the uptake of [3H]norepinephrine ([3H]NE) and [3H]dopamine and [3H]5-hydroxytryptamine ([3H]5-HT) into in vitro synaptosomes prepared from the striatum and cortex in a concentration-dependent manner. The rank order of potency for the inhibition of amine uptake is NE > dopamine > 5-HT [173]. Similar results were obtained by Ramassamy et al. [174]. These workers showed that EGb decreased the specific uptakes of [3H]dopamine, [3H]5-HT and [3H]choline by synaptosomes prepared from the striatum of mice in a concentration-dependent manner. The IC,0 values were 637 pg/rol for [3H]dopamine uptake, 803 pg/ml for [3H]5-HT uptake, >2000 pg/ml for [3H]choline uptake. However, they concluded that the inhibition of amine uptake caused by EGb appears to be non-specific, since EGb also prevents the specific binding of the dopamine uptake inhibitor [3H]GBR12783 to membranes prepared from striatum. 

Dihydrocorynantheine (86), in turn, along with other structurally related alkaloids, has been found to decrease specific [3H]-5-hydroxytryptamine (5-HT) binding to membrane preparations from rat... 

In general, diverse TA are known to bind to (a) muscarinic receptors (MR), (b) 5-hydroxytryptamine (serotonin) receptor 3 (5-HT3R), (c) al-adrenoreceptors (al-AR), or (d) a7-nicotinic receptors (a7-nAChR) thus causing different physiological effects. The corresponding mechanisms of action should briefly be addressed below. 

Shapiro DA, Kristiansen K, Kroeze WK, Roth BL. Differential modes of agonist binding to 5-hydroxytryptamine(2A) serotonin receptors revealed by mutation and molecular modeling of conserved residues in transmembrane region 5. Mol Pharmacol 2000 58 877-886. 

Hirst WD, Abrahamsen B, Blaney FE, et al. Differences in the central nervous system distribution and pharmacology of the mouse 5-hydroxytryptamine-6 receptor compared with rat and human receptors investigated by radioligand binding, site-directed mutagenesis, and molecular modeling. Mol Pharmacol 2003 64 1295-1308. 

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