<Ul> <Li> Glutamate is used at the great majority of fast excitatory synapses in the brain and spinal cord . It is also used at most synapses that are `` modifiable '' , i.e. capable of increasing or decreasing in strength . Modifiable synapses are thought to be the main memory - storage elements in the brain . Excessive glutamate release can overstimulate the brain and lead to excitotoxicity causing cell death resulting in seizures or strokes . Excitotoxicity has been implicated in certain chronic diseases including ischemic stroke , epilepsy , amyotrophic lateral sclerosis , Alzheimer 's disease , Huntington disease , and Parkinson 's disease . </Li> <Li> GABA is used at the great majority of fast inhibitory synapses in virtually every part of the brain . Many sedative / tranquilizing drugs act by enhancing the effects of GABA . Correspondingly , glycine is the inhibitory transmitter in the spinal cord . </Li> <Li> Acetylcholine was the first neurotransmitter discovered in the peripheral and central nervous systems . It activates skeletal muscles in the somatic nervous system and may either excite or inhibit internal organs in the autonomic system . It is distinguished as the transmitter at the neuromuscular junction connecting motor nerves to muscles . The paralytic arrow - poison curare acts by blocking transmission at these synapses . Acetylcholine also operates in many regions of the brain , but using different types of receptors , including nicotinic and muscarinic receptors . </Li> <Li> Dopamine has a number of important functions in the brain ; this includes regulation of motor behavior , pleasures related to motivation and also emotional arousal . It plays a critical role in the reward system ; Parkinson 's disease has been linked to low levels of dopamine and schizophrenia has been linked to high levels of dopamine . </Li> <Li> Serotonin is a monoamine neurotransmitter . Most is produced by and found in the intestine ( approximately 90 % ) , and the remainder in central nervous system neurons . It functions to regulate appetite , sleep , memory and learning , temperature , mood , behaviour , muscle contraction , and function of the cardiovascular system and endocrine system . It is speculated to have a role in depression , as some depressed patients are seen to have lower concentrations of metabolites of serotonin in their cerebrospinal fluid and brain tissue . </Li> <Li> Norepinephrine which focuses on the central nervous system , based on sleep patterns , focus and alertness . It is synthesized from tyrosine . </Li> <Li> Epinephrine which is also synthesized from tyrosine takes part in controlling the adrenal glands . It plays a role in sleep , with ones ability to become and stay alert , and the fight - or - flight response . </Li> <Li> Histamine works with the central nervous system ( CNS ) , specifically the hypothalamus ( tuberomammillary nucleus ) and CNS mast cells . </Li> </Ul>
<Ul> <Li> Glutamate is used at the great majority of fast excitatory synapses in the brain and spinal cord . It is also used at most synapses that are `` modifiable '' , i.e. capable of increasing or decreasing in strength . Modifiable synapses are thought to be the main memory - storage elements in the brain . Excessive glutamate release can overstimulate the brain and lead to excitotoxicity causing cell death resulting in seizures or strokes . Excitotoxicity has been implicated in certain chronic diseases including ischemic stroke , epilepsy , amyotrophic lateral sclerosis , Alzheimer 's disease , Huntington disease , and Parkinson 's disease . </Li> <Li> GABA is used at the great majority of fast inhibitory synapses in virtually every part of the brain . Many sedative / tranquilizing drugs act by enhancing the effects of GABA . Correspondingly , glycine is the inhibitory transmitter in the spinal cord . </Li> <Li> Acetylcholine was the first neurotransmitter discovered in the peripheral and central nervous systems . It activates skeletal muscles in the somatic nervous system and may either excite or inhibit internal organs in the autonomic system . It is distinguished as the transmitter at the neuromuscular junction connecting motor nerves to muscles . The paralytic arrow - poison curare acts by blocking transmission at these synapses . Acetylcholine also operates in many regions of the brain , but using different types of receptors , including nicotinic and muscarinic receptors . </Li> <Li> Dopamine has a number of important functions in the brain ; this includes regulation of motor behavior , pleasures related to motivation and also emotional arousal . It plays a critical role in the reward system ; Parkinson 's disease has been linked to low levels of dopamine and schizophrenia has been linked to high levels of dopamine . </Li> <Li> Serotonin is a monoamine neurotransmitter . Most is produced by and found in the intestine ( approximately 90 % ) , and the remainder in central nervous system neurons . It functions to regulate appetite , sleep , memory and learning , temperature , mood , behaviour , muscle contraction , and function of the cardiovascular system and endocrine system . It is speculated to have a role in depression , as some depressed patients are seen to have lower concentrations of metabolites of serotonin in their cerebrospinal fluid and brain tissue . </Li> <Li> Norepinephrine which focuses on the central nervous system , based on sleep patterns , focus and alertness . It is synthesized from tyrosine . </Li> <Li> Epinephrine which is also synthesized from tyrosine takes part in controlling the adrenal glands . It plays a role in sleep , with ones ability to become and stay alert , and the fight - or - flight response . </Li> <Li> Histamine works with the central nervous system ( CNS ) , specifically the hypothalamus ( tuberomammillary nucleus ) and CNS mast cells . </Li> </Ul>
what is the most abundant neurotransmitter in the nervous system
what is the most abundant neurotransmitter in the nervous system
Serotonin
Serotonin