1. 神經細胞：neuron
Dendrites：樹突；axon：軸突；axon hillock：軸丘
Soma細胞本體；myelin sheath髓鞘；node of Ravier：蘭氏節
神經膠細胞Glial cell：主要有三種
(1) Oligodendrocyte：CNS
Schwann cell：PNS
構成myelin sheath→傳速較快→node of Ranvier(蘭氏節)
(2) astrocyte：星狀細胞→提供養分，支持作用
(3) microglia：remove debris
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神經傳導的細部過程：
1. 兩種膜電位：
(1) graded potential：刺激越大，反應越大；只能傳到一段區域，後逐漸消失
(2) action potential：反應不因刺激大而更大(改變頻率)，能夠不斷的傳下去
all or none：全有全無律(超過threshold)
2. action potential sequence：depolarization→repolarization→hyperpolarization→Na-K Pump→resting potential
(1) depolarization：超過threshold(-50mv)：voltage gated ion channel open(Na+)
大量鈉離子湧入→depolarization→1ms內進入inactivation(不反應期)
必須恢復resting potential→反應才能繼續進行
(refractory period：給予頻率刺激的上限，並阻止電訊號往反方向傳遞)
(2) repolarization：超過threshold(40mv)：voltage gated ion channel open(K+)
鉀離子離開細胞→過量的鉀離子離開→形成hyperpolarization→由鈉鉀pump恢復resting potential
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1. 突觸：synapse
(1) 電性突觸：利用gap junction
(2) 化學突觸：利用neurotransmitter
Step：
動作電位→鈣離子通道打開→促進神經傳導物質的分泌→synaptic cleft→postsynaptic cell→產生EPSP (興奮性)or IPSP(抑制性)
2. 5種neurotransmitter：
(1) Acetylcholine：乙醯膽鹼
Released at the synapses，neuromuscular junction(運動終板)
對於骨骼肌，大腦：excitatory
對於心肌：inhibitory
蛇毒→可以抑制acetylcholine receptor→肌肉無法收縮
(2) Biogenic amine：compound that formed from amino acid
包括：dopamine, epinephrine, norepinephrine
與情緒相關→psychoactive
(3) amino acid
glutamate：excitatory neurotransmitter
GABA：inhibitory neurotransmitter →打開氯離子通道
(4) neuropeptide
short chain of amino acid
often called：neuromodulator→改變突觸後細胞的狀態(ex.增加受體)
oxytocin(催產素)：trust/bond/social recognition
opiate peptide：腦內啡→help deal with stress
(5) gaseous neurotransmitter
NO：relaxing smooth muscle→erection
3. Postsynaptic receptor：
1. ionotropic：
ligand-gated ion channel
when bind to neurotransmitter→→ion channel open or close→EPSP
2. metabotropic：
G-protein coupled receptor
When bind to neurotransmitter→second messenger→change in postsynaptic cell
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