B9902001 尤思涵. Dopamine and Serotonin Dopamine 4-(2-aminoethyl)benzene-1,2-diol 5-Hydroxytryptamine or 3-(2-aminoethyl)-1H-indol-5-ol Serotonin.

B9902001 尤思涵

Dopamine and SerotoninDopamine

4-(2-aminoethyl)benzene-1,2-diol

5-Hydroxytryptamine or 3-(2-aminoethyl)-1H-indol-5-ol

Serotonin

Dopamine → brain

(1)Neurotransmitter

Receptors:

1.D1 family (D1, D5 receptors)

2.D2 family (D2, D3, D4 receptors)

Three way of dopamine

1.The nigrostriatal pathway ： motor planning , movement, cognition

2.The mesocortical pathway： working memory

3.The mesolimbic pathway： motivation, experience of pleasure, reward.

(2)Neurohormonel： inhibit the release of prolactin

Location and Funtion

Serotonin →gastrointestinal tract

(1)enterochromaffin cells in the gut

intestinal movements

(2)serotonergic neurons in the CNS

mood, appetite, sleep, muscle contraction, memory, learning

(3)blood

Vasoconstrictor, hemostasis, blood clotting.

(4)some types of cells

growth factor

Location and Funtion

Conditions & Treatment

Dopaminelow dopamine → Parkinson‘s disease, social phobia, ADHD,

depressionhigh dopamine → Bipolar mania

reduce dopamine →Antipsychotic medicationsincrease dopamine →levodopa (Parkinson's Disease),

amphetamines (used for ADHD)

some antidepressants.

Serotoninlow serotonin →depression, anxiety disorders, obesity,

migraines, SIDS high serotonin → Serotonin syndrome, migraines,

gastrointestinal problems, certain

types of cardiovascularincrease serotonin → antidepressants, anti-migraine

medications. decrease serotonin → anti-nausea medications, including

odansetron

Conditions & Treatment

Dopamine-producing neurons are targets for nearby serotonin ：

Substantial Interaction

dopamine release in the dorsal striatum area of the midbrain

serotonin 2C receptor activation

EX. Chronic treatment with serotonin antidepressants

serotonin 1A receptor activation

stimulate dopamine release in the prefrontal cortex and in the midbrain

inhibit

inhibit

mesocortical pathwaymesolimbicpathway

MoodDopamine plays a central role in the

brain’s reward system, which includes inducing feelings of pleasure and positive mood states.

Serotonin is a well-known contributor to feelings of well-being.Modulation of serotonin at synapses is thought to be a major action of several classes of pharmacological antidepressants.

SleepThe majority of evidence supports involvement of

serotonin and dopamine in the mood improving effects of sleep deprivation.

SerotoninTotal sleep deprivation increases the firing rate of

serotonin neurons in different brain regions in cats and in rats.

Enhanced serotonin activity →sleep deprivationDopamineDecreases in brain dopamine receptor levels can induce

depression, sleep is thought to be accompanied by a reduction of dopamine release. 

Sleep deprivation would help to prevent dopamine from reaching low levels.

cognitive performance and sleep

AttentionDopamineThe excess dopamine causes restlessness and

hyperactivity, behaviors that are strikingly similar to those exhibited by children with ADHD.

Serotonin The scientists administered Prozac®-a well-known inhibitor

of serotonin reuptake-to the knockout mice. After ingesting Prozac®, the knockout mice showed dramatic declines in hyperactivity.

Hyperactivity may develop when the relationship between dopamine and serotonin is thrown off balance.

LearningDopamine (DA)-serotonin interactions dealing with learning and

memory functions have been apparent.increased serotonin →detrimental effect on cognitive functionsstrong DA →facilitative effect on cognitive functions

pharmacological disruption of serotonin neurotransmission results in a facilitative effect on the processing of mnemonic information by cerebral regions under strong, functional DA modulation

These effects seem to occur through the interaction of different pre- and postsynaptic DA and serotonin receptor subtypes acting as opposite systems underlying cognitive abilities.