Serotonin, a crucial neurotransmitter synthesized by enterochromaffin cells, plays a cardinal role in regulating gastrointestinal (GI) motility. With over 90% of the body's total serotonin in the GI tract, its influence on digestive processes is profound. Serotonin is swiftly released upon various stimuli, such as food boluses or certain drugs, triggering intrinsic sensory neurons in the myenteric plexus and extrinsic vagal and spinal sensory neurons. This leads to the activation of the...

Atypical antidepressants, including bupropion (Wellbutrin), mirtazapine (Remeron), nefazodone (Serzone), trazodone (Desyrel), and vilazodone (Viibryd), offer unique mechanisms of action. Bupropion weakly inhibits dopamine and norepinephrine reuptake, aiding depression treatment and smoking cessation, with a low risk of sexual dysfunction. Mirtazapine enhances serotonin and norepinephrine neurotransmission, leading to sedation, increased appetite, and weight gain. As a result, it helps treat...

The Enteric Nervous System (ENS) plays a pivotal role in regulating gastrointestinal or GI motor activity. This complex network of nerves, deeply embedded within the gut wall, responds to changes in the gut environment and receives input from both the autonomic nervous system and the central nervous system. By doing so, the ENS operates various programs tailored to the body's nutritional status and needs.
During periods of fasting, the ENS initiates the migrating myoelectric complex, a...

Neurotransmitters are essential chemical messengers within the nervous system, facilitating the communication between neurons. These chemical messengers, varying in function and effect, are critical for sustaining various aspects of neurological health and emotional well-being.

Neurotransmitters are integral to the brain's communication system, enabling neurons to transmit signals across synapses. This chemical exchange underpins various cognitive functions, including memory processes. The role of neurotransmitters in memory is multifaceted, influencing the encoding, consolidation, and retrieval of memories through their action on different neural circuits.
 Glutamate and Synaptic Plasticity
Glutamate, the brain's main excitatory neurotransmitter, is...

Tricyclic Antidepressants (TCAs), including Desipramine (Norpramin), Imipramine (Tofranil), Clomipramine (Anafranil), and Amitriptyline (Elavil), inhibit serotonin and norepinephrine reuptake and also block other receptors. They are used for depression, pain conditions, and insomnia. Common adverse effects include anticholinergic effects, sedation, orthostatic hypotension, and weight gain. They have a narrow therapeutic window and so require plasma-level monitoring. Abrupt discontinuation can...