Ch 12 Nervous System - Neurotransmitters Flashcards
neurotransmitters
chemicals used for neuronal communication w body and brain
chemical neurotransmitters
acetylcholine, biogenic amines, amino acids, peptides, novel messengers (ATP and dissolved NO and CO)
acetylcholine
CNS - motor cortex
PNS - neuromuscular junction
excitatory or inhibitory (skeletal muscle vs myocardium)
biogenic amines
catecholamines and indolamines
play roles in emotional behaviors and biological clock
catecholamines
dopamine, norepinephrine (NE), and epinephrine
indolamines
serotonin and histamine
dopamine
CNS - hypothalamus
PNS - sympathetic neurons
excitatory or inhibitory; “feel good” NT
serotonin
CNS - hypothalamus; limbic system
inhibitory
plays roll in sleep, appetite, migraines
important in mood regulation
amino acids
found only in CNS
GABA, glycine, glutamate, aspartate (NMDA)
GABA
CNS - hypothalamus; spinal cord
inhibitory
too much or too little can affect wanted and unwanted movements
peptides
substance P - mediator of pain signals
beta endorphin, dynorphin, enkephalins
act as natural opiates, reducing perception of pain
gut brain peptides - somatostatin and cholecystokinin
endorphins and enkephalins
CNS - hypothalamus; cerebral cortex
inhibitory
natural pain killer
ATP
found in both CNS and PNS
excitatory and inhibitory
introduces Ca++ wave propagation in astrocytes
provokes pain sensation
excitatory neurotransmitters
cause depolarization (eg glutamate)
inhibitory neurotransmitters
cause hyperpolarization (eg GABA and glycine)