Description: "Prozac is an antidepressant of the SSRI, or selective serotonin reuptake inhibitor class. Typical of SSRIs, Prozac increases the level of usable serotonin in the brain. High levels of Serotonin are correlated with good moods, as serotonin is largely responsible for mood regulation. But sometimes, moods can suffer if serotonin levels are too low. This animation shows how Prozac inhibits the reuptake of serotonin, thus yielding more usable serotonin for receptor binding.• Prozac's active mechanism is found within Neurons, our brains' cells. Neurotransmitters, like Serotonin, are the chemicals that make communication between theses cells possible. This communication takes place in the spaces between neurons known as Synapses. • This scene shows a presynaptic neuron on top, a postsynaptic neuron below, and the gap of synaptic space in between. The three proteins essential to serotonin's mechanism our shown in yellow, while the neurons' other proteins are rendered less prominently.• In its uninhabited mechanism, Serotonin moves circuitously from the presynaptic vesicle to the postsynaptic receptor protein where it temporarily binds.• Excess serotonin is either deactivated at the synapse by metabolizing enyzems such as monamine oxidase, or retaken back through the serotonin transporter reuptake protein as highlighted here. • Here is a detailed view of the membrane bound serotonin transporter protein based on a 2008 article in Science. As you can see, this transport protein's reuptake mechanism is a substrate-induced structural conformation of gated rocker-switches. • In Stage A, The outward-faceing open conformation is ready to receive the substrate. In Stage B or, the outward-facing occluded conformation, the substrate is bound in the primary binding site and the external gate closes. In stage C, Closure of the external gate promotes the inward-facing occluded conformation. And in stage D, The inward-facing conformation opens its gate for substrate release, this conformation is hypothetical.• During uninhibited serotonin reuptake, serotonin moves through the transport protein's gated rocker-switches smoothly. • This is Prozac, a small chirale molecule. Once Prozac locates and binds to the presynaptic reuptake protein, the protien's gating mechanism is disabled, and no longer able to transport Serotonin. • Returning to the detailed view of the reuptake protein, prozac's disabling effects are clear. Serotonin molecules are denied entrance, and the gating mechanism cannot proceed. • When the Serotonin is denied entry to the reuptake protein, it must either float in synaptic space, or interact more with the postsynaptic serotonin receptior. The more time serotonin molecules spend in these states, the more significant Prozac's antidepressant effects"