figure 8-3
Reuptake and anti depressants
(Left) Soon after a neuron releases neurotransmitters such as norepinephrine or serotonin into its synaptic space, it activates a pumplike reuptake mechanism to reabsorb excess neurotransmitters. In depression, however, this reuptake process is too active, removing too many neuro trans mitters before they can bind to a receiving neuron. (Right) Tricyclic and most second-generation antidepressant drugs block the reuptake process, enabling norepinephrine or serotonin to remain in the synapse longer and bind to the receiving neuron.