Re: Where is serotonin predominantly developed, what does it bond to, and how?

Serotonin is a neurotrasnmitter derived from the amino acid tryptophane in cells which express the necessary enzymes to convert tryptophane to serotonin.

These cells are found in the dorsal raphe nucleus in the brainstem and from there serotonin is released into several different areas of the brain. Serotonin neurotransmission (the process by which serotonin is released from one nerve cell to another across the synapse which separates them and triggers an effect on the post synaptic neuron) is involved in sleep, appetite and mood among other things. Once released from the pre-synaptic cell serotonin diffuses across the synapse and binds to post-synaptic serotonin receptors.

Binding of serotonin to its receptor occurs through non-covalent interactions (meaning no chemical bonds are made but instead the interaction occurs through electrical interactions such as charged groups in amino acids attracting each other, hydrogen bonding and hydrophobic interacions). The binding of serotonin to its receptor (there are around 14 different types) triggers the receptor to "turn on" and produce a signalling effect. These signals then have an impact on many different brain activities and antidepressant drugs such as Prozac cause an elevation of serotonin levels and have the effect of improving mood.

Hope this helps!
Gabriel Vagas MD/PhD

References:
Molecules and Mentall Illness. By Samuel H. Barondes. Scientific American Library, USA, 1993. 215p.

Drugs and the Brain. By Solomon H. Snyder, Scientific American Books: Distributed by W.H. Freeman, USA, 1996. 228p.