1. Chapter 1 Organization of the Nervous System
Hypothalamus

2. Outline Function of the Hypothalamus Regulation of Body Temperature
Autonomic Nervous System

3. Reference Text Book

4. I. Function of the Hypothalamus

5.  Hypothalamus
Tu :19.17

6. Hypothalamic Functions
Food Intake
Water Balance
Sleep/wake cycle
Emotions and behavior
Circadian
Endocrine Functions
Body Temperature
Autonomic Nervous System

7. Food Intake
Ventromedial and Paraventricular Nuclei are satiety centers
Lesion causes obesity
Through disrupting satiety input to the periventricular nucleus
Lateral HT is feeding center
Stimulation cause food and water intake
Lesion causes starvation behavior
Through damage the medial forebrain bundle, leading to neglect syndrome （偏侧空间失调症） – no motivation to eat

8. Water Balance
Thirst center in the hypothalamus (supraotic nucleus) is stimulated by:
Cellular dehydration
Decreased salivary production
Increased blood osmotic pressure
Decreased blood volume
Thirst center response
Release vasopressin
Cause sensation of thirst

9. Sleep/Wake Cycle: suprachiasmatic nuc is biological clock
preoptic nuc can initiate sleep
lat HT can change cortical arousal
post HT lesion can cause coma or impaired arousal

10. Emotions and Behavior Ventromedial lesions can cause viciousness/rage
Posterior HT stimulates sympathetic functions
Anterior HT stimulates parasympathetic functions
Mamillary nuclei recent memory

11. Circadian
Almost all land animals coordinate their behavior according to circadian rhythms
Suprachiasmatic Nuclei (SCN)

12. Circadian Rhythms of Physiological Functions

13. Endocrine Function Regulation of Adenohypophysis
Secretion of Hormones (Vasopressin and Oxytocin)

14. Functions of the Hypothalamus
Food intake
Water balance
Sleep/wake cycle
Emotions and behavior
Circadian
Endocrine Function
Body temperature
Autonomic Nervous System

15. II Energy metabolism and body temperature
哺乳类 mammalia interstitial fluid hydrostatic pressure 扬子鳄

16. Reference
Unit VIII
P 483 – 485

17. Section 1 Energy Metabolism

18. Metabolism
Anabolism
Catabolism
material
synthesis
require
energy
material
breakdown
release
energy
material
metabolism
energy
metabolism

19. Energy storage, liberation, transfer and utilization
anaerobic

20. Energy balance Energy input = energy output Food heat heat
ATP
cellular functions heat
Consumption reflex estate evaluate
metabolism
Food heat

21. Metabolic Rate
The amount of energy liberated from a living organism per unit of time
Expressed in terms of the rate of heat liberation during the chemical reactions
fire

22. Measurement of the metabolic rate
Direct calorimetry
Indirect calorimetry
Caloric value / thermal equivalent of food
Oxygen consumption / thermal equivalent of oxygen （1 L）
Respiratory quotient （CO2 / O2）
封闭 sealed apparatus consumption

24. calory

25. Factors that affect the metabolic rate
Exercise - increase in metabolic rate
Ingestion of food - Increase metabolic rate
The specific dynamic action of protein
Emotional state
Environmental temperature
20-30 °C have stable metabolic rate
< 20 or >30°C , metabolic rate is increased
Other factors (sleep, sex, age, etc.)
High – protein meal shivering

26. Component of Energy Expenditure

28. Basal metabolic rate (BMR)
minimum level of energy required to exist
a person is at basal condition (complete rest)
useful for diagnosing the diseases:
Hyperthyroidism, hypothyroidism

29. Basal conditions Fasted for at least 12 hours
After a night of restful sleep
No strenuous activity is performed for at least 1 hour before the test
All psychic and physical factors that cause excitement must be eliminated
The temperature 25 – 30℃
No physical activity is permitted during the test
诊断 diagnose

30. Section 2 Body temperature

31. Skin and Core Temperature
Skin temperature
the temperature of the skin and tissues immediately underlying the skin.
rises and falls with the temperature of the surroundings
Core temperature
the temperature of the deep tissues of the body – the “core” of the body.
remains almost constant, varying not more than 1 °C
Rectal T: °C
Oral T: °C
Axillary T: °C
axil

32. Range of Body Temperature

33. Factors affecting normal temperature
Circadian rhythm
In the early morning, the body T is the lowest.
In late afternoon or early evening, it is the highest.
Age
Newborn child > adult > old person
Sex
Women > man ℃
Muscular activity
Other factors: emotion, eating, change in climate
规律的 disciplinary

34. Heat Production BMR of all the cells Extra metabolism caused by
muscle activity
hormone (thyroxine, growth hormone and testosterone)
the effect of epinephrine,
norepinephrine and sympathetic stimulation on the cells
increased chemical activity in the cells themselves

35. Heat Loss The major organ to loss heat is the skin
Blood flow to the skin from the body core provides heat transfer
接触 touch conduct

36. Effect of Environment air Temperature
on Conductance of Heat from the Body Core to the Skin Surface

37. Methods of heat loss from the skin to the surroundings
radiation

38. Evaporation 1) Insensible perspiration 2) Sweating
Innervated mainly by sympathetic cholinergic nerve (acetylcholine)
Caused by nervous reflex
Mechanism of sweat secretion
Primary secretion
reabsorption
Sweat (urea, lactic acid, K+ )

39. Regulation of the body temperature
Behavioral control of the body temperature
Autonomic control of the body temperature

41. Feedback mechanisms of regulation of the body temperature
Temperature receptor
Peripheral temperature receptor
Locations: skin, mucous, abdominal viscera
Types: cold receptor and warmth receptor
cold receptor > warmth receptor
Central temperature receptor
Locations: spinal cord, preoptic and anterior hypothalamic area of the hypothalamus (PO/AH)
Types: heat-sensitive neurons and cold-sensitive neurons
Temperature-regulating center
1) The thermoregulating center is mainly in the hypothalamus
2) The PO/AH area is the basic thermostatic temperature controlling center

42. Feedback mechanisms of regulation of the body temperature
Efferent pathways: Control of the heat loss and heat production
Control of the skin vascular tone and sweating by sympathetic nerve system
Changes of the muscular tension by somatic motor nerve system
Control of the metabolic rate by altering the function of endocrine system, mainly the hormone secretion of the thyroid glands or adrenal medulla
glucose

43. “Set-point” 37 °C PO/AH area T > 37 °C Production < loss
Concept of a “set-point” for temperature control
The set-point of the normal body is about 37 °C
PO/AH area play the role of the “set-point”

45. Fever

46. III Autonomic Nervous System
P24 – 28
P 478 – 482

47. Section 1. Basic of the ANS
Including
parasympathetic
sympathetic
enteric divisions
Coordinates cardiovascular, respiratory, digestive, excretory and reproductive systems
The enteric system
an independent nervous system responsible for regulation of digestive functions.

48. Somatic and Autonomic Nervous System

49. Somatic and Autonomic Nervous System
Smooth and cardiac muscle and glands
Unconscious regulation
Target tissues stimulated or inhibited
Two synapses
Acetycholine by preganglionic neurons and ACh or norepinephrine by postganglionic neurons
Somatic
Skeletal muscle
Conscious and unconscious movement
Skeletal muscle contracts
One synapse
Acetylcholine

50. Sympathetic Division
Preganglionic cell bodies in lateral horns of spinal cord T1-L2

51. Parasympathetic Division
Preganglionic cell bodies in nuclei of brainstem or lateral parts of spinal cord gray matter from S2-S4
Preganglionic axons from brain pass to ganglia through cranial nerves
Preganglionic axons from sacral region pass through pelvic nerves to ganglia
Preganglionic axons pass to terminal ganglia within wall of or near organ innervated

52. Parasympathetic and sympathetic nerve distribution

53. 2. Neurotransmitters and Neuroreceptors
Acetylcholine and Norepinephrine
All preganglionic neurons are cholinergic
Parasympathetic post ganglionic neurons are cholinergic
Sympathetic post ganglionic neurons are adrenergic except
Sympathetics innervating sweat glands, blood vessels in skeletal muscle, and piloerection muscles are cholinergic

54. Neurotransmitters SOMATIC NERVOUS SYSTEM Striated ACh muscle
Heart
Sm. mus.
Glands
ACh NE
AUTONOMIC NERVOUS SYSTEM
Sympathetic
ACh
E, NE
Ad. M.
 
ACh
Sweat
glands
Heart
Sm. mus.
Glands
ACh
Parasympathetic

55. Section 3 Function of the Sympathetic and Parasympathetic Nerve

56. SNS Sympathetic nervous system prototypically “fight” or “flight”.
Associated with increased
energy expenditure
cardiopulmonary adjustments for intense activity,
blood flow adjustments for maximum energy expenditure.

57. SNS - Fight & Flight Reaction
You’re walking alone at night and all the sudden you hear an unfamiliar noise near by… In a matter of seconds,
your heart rate increases dramatically,
blood vessels in your skeletal muscles dilate,
blood vessels in the visceral muscles constrict,
digestion is ceased,
your liver ramps up glucose release,
your pupils dilate,
salivary production decreases,
sweat increases.

58. Parasympathetic Nervous System
If that noise turns out to be the result of wind, then the body is returned to “pre-noise” state.
This is the job of the parasympathetic nervous system.

59. Autonomic Nervous System
Parasympathicus
Wind down, relaxation, digestion
Dominated by Acetylcholine
Sympathicus
Fight & Flight Reaction
Dominated by Noradrenaline (Adrenaline)
Fear, exercise, rage

60. Interactions of the ANS
Most visceral organs are innervated by both types of nerves.
Most blood vessels are innervated only by sympathetic nerves.
PS activity dominates the heart and GI tract.
Activation of the sympathetic division causes wide spread, long-lasting mobilization of the fight-or-flight response.
PS effects are highly localized and short lived.