Question

Explain in detail the physiological functions and mechanisms of action of a neurotransmitter (Serotonin) and explain how drugs can alter their function.

Answer 1

Functions

1)It is an important neurotransmitter

2)Helps to regulate mood and social behaviour,digestion,sleep and memory

3)Constriction of smooth muscles

4)Keeps a sleep-wake cycle and forms a internal clock.

5)Also helps in creating happy mood and sense of well being

Mechanism of action

Serotonin binds to the reversibly binds to the post synaptic receptor to induce a postsynaptic neuron.It binds to auto receptors on the pre synaptic neurons and released serotonin.After its use it is broken down by monoamine oxidase,as it is a part of monoamine group of neurotransmitters.

Drugs

Antidepressants contain monosmine oxidase inhibitors which prevent the breakdown of serotonin which inturn increases its concentration in the brain

Psychedelic drugs

Induce the release of serotonin

Increased dose of antidepressants can lead to serotonin syndrome

Antiemetics inhibit the release of serotonin