Neurotransmitters
Neurotransmitter | Inhibitory? Excitatory? Neither? Both? | Anatomy/Pathway in Brain | Major Function | Receptors |
Glutamate | Excitatory | Everywhere / very widespread | Excitation; learning & memory specifically associated with NMD A receptors | lonotropic: AMPA, NMDA, kainate; Metabotropic: mGluR1-mGluR8 |
GABA | Inhibitory | Everywhere / very widespread | Inhibition; regulation of neural activity | lonotropic: GABA-A, GABA-C; Metabotropic: GABA-B |
Acetylcholine (ACh) | Excitatory in most cases | Basal forebrain → cortex & hippocampus; Midbrain → hindbrain | Arousal, attention, learning, memory, muscle contraction | lonotropic: Nicotinic; Metabotropic: Muscarinic |
Dopamine (DA) | Both | VTA → nucleus accumbens & cortex (mesolimbocortical); Substantia nigra → basal ganglia/striatum (mesostriatal) | Motivation & reward; initiation of All GPCRS voluntary movement | |
Norepinephrine (NE) | Both | Locus coeruleus → forebrain; Lateral tegmental area → brainstem & spinal cord | Alertness, mood, attention/vigilance; also sleep/arousal, reward/feeding, All GPCRs learning & memory, fight-or-flight | |
Serotonin (5-HT) | Both | Raphe nuclei → everywhere, including spinal cord | Mood, sleep, sexual behavior, anxiety | Most are GPCRs; 5-HT3 is ligand-gated ion channel |
Endogenous Opioids | Not specified in video | Synthesized throughout brain → Pain, pleasure, mood projections throughout CNS | Not specified in slides | |
Nitric Oxide | Not specified in video | Produced mainly in dendrites; can travel postsynaptic → presynaptic as a retrograde transmitter | Long-term potentiation (LTP); blood-flow regulation | No receptors involved; diffuses into target cell and activates second messengers |
Endocannabinoids | Not specified in video | Produced mainly in dendrites; released postsynaptically → presynaptically (retrograde signaling) | Synaptic plasticity, mood, appetite, pain, sleep | Cannabinoid receptors; CBIR specifically mentioned |