Olga Vajnerov

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Olga Vajnerová2. LF UK Praha
Hypothalamus
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Hypothalamus, a major control headquarters for
the limbic system

• Hypothalamus
• Cortex
• Thalamus
• Temporal lobe
• Basal ganglia
• Septum
• Paraolfactory area

cingulate gyrus Parahippocampal
gyrus Orbitofrontal cortex
Anterior nuclei
Hippocampus Amygdala
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(No Transcript)
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Functions of hypothalamus
Neurosecretion oxytocin, ADH Statins,
liberins Temperature control Homeostasis Biorhythm
s Transmission of emotions Hunger, thirst
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Functions of hypothalamus
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Relation to autonomic function Parasympathetic
responses Urinary bladder contraction Sympathetic
responses Increased adrenal medullary
secretion Vasoconstriction Stress fight or
flight
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Cardiovascular regulation
Arterial pressure Heart rate
Specific cardiovascular control centres are in.
Reticular regions of the pons and
medulla Cardioexcitatory area Cardioinhibitory
area Vasomotor area Via Sympathetic and
Parasympathetic nerves
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Influence on respiratory and gastointestinal
reflexes Olfactory stimulus from
paleocortex Signals to visceromotor centres i
medulla nausea, vomiting
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Transmission of emotions from limbic
system Rage, anxiety and fear, joy, sadness Is
connected with visceromotor and somatomotor
reaction Hear rate, breathig rate, vasomotor
reaction pale or red skin, sweat glands,
gastrointestinal motility and secretion, smooth
muscle in skin, shivering
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Biological rhythms Suprachiasmaticus nuclei
retinohypothalamic tract Pacemaker of circadian
rhythms Sleep wake cycle ACTH
secretion Melatonin secretion Body temperature
rhythm Activity patterns of animals
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• Regulation of body water
• Thirst center
• Lateral hypothalamus
• Osmoreceptors when the EF is too concetrated
  develops intense desire to drink water
• 2. Antidiuretic hormone

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Gastrointestinal and feeding regulation Hunger La
teral hypothalamic area, stimulation extreme
hunger, appetite, desire to search for
food Damage to this area lethal
starvation Satiety Ventromedial
nuclei Stimulation stop eating Destruction
hunger centers overactive, obesity
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Regulation of body temperature
Temperature regulating centers Temperature
receptors
1. Peripheral Skin receptors (cold and warm) Deep
body temperature receptors Spinal cord, abdominal
viscera and great veins 2. Central Temperature
detectors in hypothalamus Heat sensitive neurons,
cold sensitiv neurons Praeoptic area
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Posterior hypothalamus integrates the central and
peripheral temperature sensory signals
Control Heat-producing Heat- conserving
reaction of the body
Set point crucial temperature level
37.1ºC Feedback gain for body temperature control
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Temperature-decreasing mechanisms
Vasodilation of skin blood vessels
Inhibition of the sympathetic centers in the
posterior hypothalamus
Sweating Praeoptic area, via autonomic pathways
to the spinal cord Sympathetic but cholinergic
Decrease in heat production Inhibition of
shivering and thermogenesis
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Temperature-decreasing mechanisms
Vasodilation of skin blood vessels
Inhibition of the sympathetic centers in the
posterior hypothalamus
Sweating Praeoptic area, via autonomic pathways
to the spinal cord Sympathetic but cholinergic
Decrease in heat production Inhibition of
shivering and thermogenesis
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Temperature-decreasing mechanisms
Vasodilation of skin blood vessels
Inhibition of the sympathetic centers in the
posterior hypothalamus
Sweating Praeoptic area, via autonomic pathways
to the spinal cord Sympathetic but cholinergic
Decrease in heat production Inhibition of
shivering and thermogenesis
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Temperature-increasing mechanisms When the body
is too cold
1. Vasoconstriction of skin blood vessels
Stimulation of the sympathetic centers in the
posterior hypothalamus
2. Piloerection via autonomic pathways to the
spinal cord Sympathetic stimulation causes
arrector pili muscles to contract
3. Increase in heat production,
thermogenesis Shivering, sympathetic excitation
of heat production, Thyroxin secretion
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3. Increase in heat production,
thermogenesis Shivering Primary motor center for
shivering in the dorsomedial portion of the
posterior hypothalamus Excited by cold signals
from the skin and spinal cord Tr
hypothalamoreticularis, hypothalamospinalis to
spinal motoneurons Non rhytmical signals,
increase the tone of the skeletal
muscles Probably feedback oscillation of the
muscle spindle stretch reflex Sympathetic
excitation of heat production Chemical
thermogenesis, E and NE uncouple oxidative
phosphorylation, energy in the form of heat but
do not cause ATP to be formed Thyroxin secretion
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Sympathetic excitation of heat production Chemical
thermogenesis, E and NE uncouple oxidative
phosphorylation, energy in the form of heat but
do not cause ATP to be formed Thyroxin
secretion
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Olga Vajnerováusing Mital Patel presentation
Hypothalamic-hypophysial system.
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Structure of hypothalamus and pituitary gland

• The pituitary gland together with the
  hypothalamus provide endocrine control of many
  major physiological function

• Hypothalamus
• Located below the thalamus just above the
  brain stem
• Subdivided into a number of nuclei
  paraventricular, supraoptic, arcuate,

• Pituitary gland
• Located inside skull below hypothalamus
• Has 3 divisions Adenohypophysis (ant),
  Neurohypophysis (post) and the pars intermedia

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Adenohypophysis

• Linked to hypothalamus via hypophyseal-portal
  system in the infundibulum
• Connection allows hypothalamus to
  stimulate/inhibit 5 distinct pituitary cell
  types
• 1. somatotropes -human growth hormone
• 2. corticotropes - adrenocortictropin
• 3. Thyrotropes - TSH
• 4. Gonadotropes LH and FSH
• 5. Lactotropes - Prolactin

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Negative feedback (autoregulation)
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Hypothalamic hormones Adenohypophysis
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Blue peptides yellow - steroids Light blue
glycoproteins orange tyrosine derivates
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Neurohypophysis

• Connected to the hypothalamus via infundibulum
• Hormones made in nerve cell bodies in the
  hypothalamus, are transported down the nerve to
  the neurohypophysis
• Secretes two peptide hormones
• oxytocin from paraventricular
• nucles
• ADH from supraoptic nucleus
• Axons reach terminal on inf hypophyseal artery to
  enter general circulation

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Hypothalamic hormones Neurohypophysis
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QUESTION

• PATIENT
• EXTREME THIRST
• EXCESSIVE DILUTED URINATION DAY AND NIGHT
• DEHYDRATION
• WHATS THE DIAGNOSIS?

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QUESTION

• PATIENT
• EXTREME THIRST
• EXCESSIVE DILUTED URINATION DAY AND NIGHT
• DEHYDRATION
• WHATS THE DIAGNOSIS?

DIABETES INSIPIDUS ADH DEFICIENCY