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自主神經系統及下視丘
Autonomic Nervous System
Hypothalamus
Principle of Neuroscience (第五版Ch 47)
楊靜修 老師



Parasympathetic NS:
gain and conserve energy for
the body
1. increase secretion & motility
(salivary gland, GI)
2. decrease HR
Sympathetic NS:
energy-consuming
1. Decrease GI
2. Increase HR, BP
3. Bronchi relax
4. Blood glucose increase
5. NE, Epi release increase
ANS (屬PNS但可反應CNS)
-大腦的天線 (接收訊習)
-將大腦訊習傳給全身臟器
(ANS可以反應大腦許多功能
及問題，所以有機會為
biomaker)
Parasympathetic nervous system
Sympathetic nervous system
Reflex arch of autonomic nervous system
Visceral
receptors
integrated
stimulation

Visceral
effector
Afferent autonomic
pathway
CNS
Efferent autonomic
pathway
CNS: central nervous system
+
+ or -
Figure 49-1 Anatomical organization of the somatic and autonomic motor pathways.
Anatomy
IML: intermediolateral horn
Figure 49-2 Anatomical organization of the sympathetic preganglionic and postganglionic axons.
交感神經: IML: intermediolateral horn
IML--para v.c. 換cell--回spinal nerve (8%) 分泌ACh
--分支出去分泌NE
IML--pre v. 換cell--分泌NE
IML--adrenal medulla--分泌NE
C fiber
T1
75%
8% ACh
其他為NE
L3
ACh
1.分布較少
2.反應較不連續
且為局部作用
S2-S4
22對
Summary
Autonomic Nervous System
• Sympathetic nervous system:
– Spinal nerves T1-L3
• Parasympathetic nervous system:
– Cranial nerves III, VII, IX, X
– Spinal nerves S2-S4
• Enteric nervous system:
– Myenteric (Auerbach’s) plexus
– Submucous (Meissner’s) plexus
Physiology
Transmission Process
Biosynthesis of Neurotransmitters (NE)
Biosynthesis of Neurotransmitters (ACh)
Mechanisms of signal transduction
NE receptor:
Sympathetic
nervous system
Adrenergic receptor
短
a1-receptor:
contraction BP 
b1-receptor:
HR 
contractility 
b2-receptor:
relaxation
長
ANS
(Autonomic nervous system)
長
短
M2 receptor
Parasympathetic
nervous system
ACh receptors
Nicotinic receptor: N receptor
Muscarinic receptor: M receptor
Voluntary command: Move!
Motor neuron
Involuntary command: Rest & digest.
Involuntary command: Emergency!
以作用到的receptor種類決定何種反應
CNS
Prejunctional autoreceptors
Biosynthesis of Neurotransmitters (NE)
In terminal
Rate limiting step
In vesicle
Tissue, blood, urine可檢測濃度
MAO: monoamine oxidase
COMT: Catechol-O-methyl transferase
Biosynthesis of Neurotransmitters (ACh)
In terminal
合成之酵素
choline-O-acetyltransferase
degradation
Mechanisms of signal transduction
Neurotransmitter receptors in the peripheral ANS (adrenoceptors)
Neurotransmitter receptors in the peripheral ANS (cholinoceptors)
Prejunctional autoreceptors
T1
L3
S2-S4
HR 以副交感影響為主
1. 不完全什麼臟器
都有兩者控制
2. 興奮及抑制都有
副交感系統過度
興奮並不好 但是
維持生存所必需
Autonomic neurons use a variety
of chemical transmitters
• Ganglionic transmission involves both fast and
slow synaptic potentials
• Norepinephrine and acetylcholine are the
predominant transmitters in the ANS
• ATP and adenosine have potent extracellular
actions
• Many different neuropeptides are present in
autonomic neurons
Figure 49-6 Both acetylcholine (ACh) and a luteinizing hormone-releasing hormone (LHRH)-like
peptide are released by presynaptic cells at synapses in the sympathetic chain ganglia in
the bullfrog. The two transmitters produce different types of postsynaptic potentials in
different postganglionic neurons because of their actions on different receptors. .
A central autonomic network
coordinates autonomic function
Central autonomic network
Brain stem and spinal circuits
Baroreceptor reflex
ANS
sympathetic NS parasympathetic NS
Neuronal Regulation of Cardiovascular System
Baroreceptor Reflex Response (BRR)
vasomotor
center
 tonic excitation
交感神經系統
副交感神經系統
Figure 49-9 Pathways that distribute visceral sensory information in the brain.
Figure 49-10 Pathways that control autonomic responses.
Autonomic pharmacology
• Ganglionic blockers (transmission and receptor)
-block sympatheric and parasympathetic nerve activity (other
factor)
• Drugs that inhibit synthesis of neruotransmitter
• Drugs that inhibit release of neruotransmitter
• Drugs that promote release of neruotransmitter
• Drugs that interfere with storage of neurotransmitter
• Drugs that affect neuronal uptake
• Drugs that inhibit metabolism of neurotransmitter
• Drugs that block autonomic receptors
• Drugs that stimulate autonomic receptors
Adrenoceptor-activating drugs
Adrenoceptor-antagonist drugs
Chlinoceptor-activating & chlinesterse-inhibiting drugs
Cholinoceptor-blocking drugs
Drugs that inhibit synthesis of neruotransmitter
Drugs that interfere with storage of neurotransmitter
Drugs that affect neuronal uptake
Drugs that inhibit release
of neruotransmitter
Drugs that promote release of neruotransmitter
Drugs that stimulate autonomic receptors
Drugs that block autonomic receptors
Drugs that inhibit metabolism
of neurotransmitter
• Adrenergic transmission:
Uptake
Drugs that affect neuronal
uptake and inhibit synthesis
of neruotransmitter
Drugs that promote release
of neruotransmitter
Drugs that inhibit metabolism
of neurotransmitter
Drugs that interfere with storage
of neurotransmitter
Drugs that inhibit release
of neruotransmitter
Drugs that stimulate autonomic receptors
Drugs that block autonomic receptors
• Cholinergic transmission:
Effects of drugs:
mechanism
The Hypothalamus Integrates
Autonomic and Endocrine
Functions With Behavior
‘head ganglion’ of ANS
Hypothalamus:
Homeostasis
內分泌系統之控制中樞
飽食中樞, 飲水中樞, 體溫調節中樞, sexual behavior & 血壓調控,
sleep/wake, circadian rhythms
Neuroendocrinology
External environment
Pituitary gland
Hypothalamus
Internal condition
Nervous system
Hypothalamus
Posterior pituitary
Anterior pituitary
The hypothalamus serves this integrative function by
regulation of five basic physiological needs:
• It controls blood pressure and electrolyte composition by a set of
regulatory mechanisms that range from control of drinking and salt
appetite to the maintenance of blood osmolality and vasomotor tone.
• It regulates body temperature by means of activities ranging from
control of metabolic thermogenesis to behaviors such as seeking a
warmer or cooler environment.
• It controls energy metabolism by regulating feeding, digestion, and
metabolic rate.
• It regulates reproduction through hormonal control of mating,
pregnancy, and lactation.
• It controls emergency responses to stress, including physical and
immunological responses to stress by regulating blood flow to
muscle and other tissues and the secretion of adrenal stress
hormones.
The Hypothalamus Contains Specialized
Groups of Neurons Clustered in Nuclei
重點:下視丘各核區參與之生理功能
4 g/1400 g adult human brain weight
重點:下視丘各核區參與之生理功能
LHA


PVN
MPO


AH


SCN
DMH
SON
VMH 
AN

PHA
Figure 49-11 The structure of the
hypothalamus.

DMH
LHA

SON 
AN

VMH 
The Hypothalamus Controls
the Endocrine System
下視丘
前葉
甲狀腺素
Guillemin and Schally, 1977 Nobel Prize
內分泌系統簡介
下視丘
腦下垂體
甲狀腺
腎上腺
性腺
Figure 49-12 The hypothalamus controls the pituitary gland both directly
and indirectly through hormone-releasing neurons.
PVN
Figure 49-13 The paraventricular nucleus of
the hypothalamus is a microcosm of the
autonomic and endocrine control systems.
Magnocellular Neurons Secrete
Oxytocin and Vasopressin Directly
From the Posterior Pituitary
Table 49-2 Hormones of the Posterior Pituitary Gland
Name
Vasopressin
Oxytocin
Structure
Function
H-Cys-Tyr-Phe-Gln-Asn- Vasoconstriction, water
Cys-Pro-Arg-Gly-NH2 S-S resorption by the kidney
H-Cys-Tyr-Ile-Glu-AsnCys-Pro-Leu-Gly-NH2 S-S
PVN (paraventricular nucleus)
SON (supraoptic nucleus)
後葉
Parvocellular Neurons Secrete
Peptides That Regulate Release
of Anterior Pituitary Hormones
Table 49-3 Hypothalamic Substances That Release or Inhibit the Release of Anterior
Pituitary Hormones
Hypothalamic substance
Anterior pituitary hormone
Releasing
Thyrotropin-releasing hormone (TRH)
Thyrotropin, prolactin
Corticotropin-releasing hormone (CRH)
Adrenocorticotropin, β -lipotropin
Gonadotropin-releasing hormone (GnRH) Luteinizing hormone (LH), follicle-stimulating
hormone (FSH)
Growth hormone-releasing hormone
Growth hormone (GH)
(GHRH or GRH)
Prolactin-releasing factor (PRF)
Prolactin
Melanocyte-stimulating hormonereleasing factor (MRF)
Inhibiting
Melanocyte-stimulating hormone (MSH), β endorphin
Prolactin release-inhibiting hormone
(PIH), dopamine
Growth hormone release-inhibiting
Growth hormone, thyrotropin
hormone (GIH or GHRIH; somatostatin)
Melanocyte-stimulating hormone release- Melanocyte-stimulating hormone (MSH)
inhibiting factor (MIF)
前葉
TRH, CRH, GnRH, GRH GIH, PRF PIH, MRF
前葉
下視丘
前葉
甲狀腺
下視丘
前葉
性腺
下視丘
前葉
腎上腺皮質素
前葉
壓力
Short-term & long-term
nervous system & endocrine system
神經系統
內分泌系統
內分泌系統
內分泌系統
全自動控溫系統
Homeostasis
set point, receptor, effector
全自動控溫系統
Homeostasis
set point, receptor, effector
Temperature Regulation
Receptor
(hypothalamus)
AH/POA
heat sens. cell 2/3
cold sens. cell 1/3
PH
Heat conservation
(shivering)
AH
Heat dissipation
(sweat)
Glucostatic Hypothesis of Appetite
Regulation
• Satiety Center (飽食中樞)-VMH
• Feeding Center (餵食中樞)-LHA
• glucostats: 位於VMH 內，其glucose 利用
可控制 VMH 細胞活性
VMH
- LHA
eat
Relation to Cyclic Phenomena
Infradian (longer than one day)
menstral cycle
Circadian (approx. one day)
sleeping, body temperature, various hormones, drinking,
locomotor activity…
Ultradian (shorter than one day)
feeding, respiration, heart rate, nerve impulse discharge
Circadian rhythm: light  signal from retina  SCN
Circadian Rhythms
Witte et al. 1998, Physiology & Behavior
Sleep-Awake Circuit
Awake Pathway
Sleep Pathway
Sleep center: GABA
1.
2.
LDT: laterodorsal tegmental nuclei, PPT: pedunculopontine
TMN: tuberomammillary nucleus, Raphe: raphé nuclei, LC: locus coeruleus
VLPO: ventrolateral preoptic nucleus
T1
75%
8% ACh
L3
ACh
1.分布較少
2.反應較不連續
且為局部作用
S2-S4
Hypothalamus:
內分泌系統之控制中樞 (PVN, SON, AN, ME...)
Homeostasis
飽食中樞 (VMH, LHA), 飲水中樞 (CVO, SFO, MPO), 體溫調節中樞 (PH, AH, POA),
sexual behavior, 血壓調控(PVN...), sleep (VLPO)/wake (TMN, LH), circadian rhythms (SCN)
Neuroendocrinology
External environment  Hypothalamus  pituitary gland (Hormones)
Internal condition
nervous system (head ganglion of ANS)
Hypothalamus
Posterior pituitary
Anterior pituitary