roles of serotonin

Question 0

what drugs can be used to increase the levels of serotonin in the synaptic cleft and how do they work ?

Answer 0

fenfluramine- reuptake blocker

P-chloroamphetamine- blocks reuptake transporter and causes the release of any serotonin in the cytosol

Question 1

when does serotonin suppress appetite?

Answer 1

when there is increased levels in the synaptic cleft

Question 2

what serotonin receptors are thought to be involved in appetite?

Answer 2

5HT2c because rats without this receptor became obese

Question 3

what is the link between serotonin and aggression?

Answer 3

low levels of serotonin in the synaptic cleft
patients tend to have low levels of 5HIAA in the CSF
affective aggression pathway- basolateral nuclei of the amygdala to lateral hypothalamus to PAG

Question 4

what is the link between serotonin and depression?

Answer 4

low levels of serotonin seem to be implicated in depression
SSRIs are used in the treatment to block reuptake transporter - these have contradictory effects compared to fenfluramine in that they increase cravings for carbs

Question 5

what is the link between serotonin and alcohol dependence ?

Answer 5

low levels of serotonin are thought to increase your need for alcohol
thought to interfere with serotonin involved with the mesolimbic pathway involved in reward
fenfluramine helped to reduce dependence

Question 6

what is the link between serotonin and sleep onset ?

Answer 6

precursor of serotonin is trytophan and serotonin can be metabolised to melatonin in the pineal gland which is involved in inducing sleep
therefore taking trytophan before sleep can reduce the onset of sleep
involved in circadian rhythm because the suprachiasmatic nucleus which controls this physiological rhythm receives dense serotonergic inputs