Hypothalamus HY

Question 1

hypothalamus regulates ____________

via regulation of:

Answer 1

hypothalamus regulates WHOLE BODY HOMEOSTASIS

via regulation of:

• ANS
• endocrine system
• somatic motor activity (drive-related behaviors)

Question 2

magnocellular system

Answer 2

• comprised of PVN (paraventricular) and SON (supraoptic) nuclei
• LARGE diameter neurons synthesize hormones (oxytocin, ADH)
• hormones transported to POSTERIOR pituitary for release into systemic circulation

Question 3

lactation reflex
afferent = _________
efferent = _________

Answer 3

lactation reflex
afferent = NEURAL
efferent = HORMONAL (oxytocin)

-neural stimulus from baby suckling –> dorsal column –> neurohypophusis –> oxytocin released –> milk letdown

Question 4

parvicellular system

Answer 4

• anterior lobe
• SMALL diameter hypothalamic neurons produce releasing and inhibiting factors that modulate synthesis and secretion of ANTERIOR pituitary hormones
• influences the pituitary via vasculature (hypophyseal portal vessels)

Question 5

hypothalmic substances that inhibit/stimulate release of pituitary hormones (and their pituitary correlate)

Answer 5

GnRH --> FSH, LH
GHRH --> GH
Somatostatin --> GH (inhibitory)
TRH --> TSH
Dopamine --> prolactin (inhibitory)
CRH --> ACTH

Question 6

CRH

Answer 6

• released by hypothalamus
• in response to stress
• causes ACTH release from pituitary
• ACTH: cortisol release from adrenal gland
• feedback signal = cortisol

Question 7

medial preoptic area

Answer 7

• TEMPERATURE regulation
• MALE sex behavior
• PARENTAL behavior
• sexually dimorphic nucleus

Question 8

superchiasmatic nucleus

Answer 8

Circadian Rhythm Center

• master clock of brain
• day/night rhythms
• retinal input

Question 9

paraventricular and supraoptic nuclei

Answer 9

• synthesis of oxytocin and vasopressin
• autonomic regulation
• stress axis
• metabolism

Question 10

anterior nucleus

Answer 10

• temperature regulation

- HEAT DISSIPATION

Question 11

arcuate nucleus

Answer 11

food intake and metabolism

-regulates feeding by responding to LEPTIN

Question 12

periventricular nucleus

Answer 12

reproductive cycles

Question 13

Korsakoff’s Syndrome

Answer 13

• destruction of mamillary bodies (and DMN)
• causes confabulatory amnesia)
• associated with poor diet and alcoholism

Question 14

posterior nucleus

Answer 14

heat CONSERVATION

Question 15

heat dissipation vs heat conservation

Answer 15

Dissipation:

• preoptic area (POA)
• anterior hypothalamic area (AH)

Conservation
-posterior hypothalamus

Question 16

which nuclei control endocrine system?

Answer 16

• supraoptic nucleus (SON)

- PVN (periventricular)

Question 17

which nuclei control ANS?

Answer 17

-PVN (periventricular)

descending projections to craniosacral/thoracolumbar regions

Question 18

which nuclei control body temp?

Answer 18

• anterior (AH)

- POA (preoptic area)

Question 19

which nuclei control day night rhythms?

Answer 19

-SCN (superchiasmatic)

Question 20

which nuclei control food intake and metabolism?

Answer 20

• VMN (satiety)
• arcuate (response to leptin)
• DMH
• PVN
• Lateral (satiety)

Question 21

which nuclei control sleep wake cycles?

Answer 21

• AH (anterior)
• POA (preoptic area)
• posterior hypothalamus

-melatonin

Question 22

median eminence

Answer 22

• swelling on base on hypothalamus on ventral surface
• has rich plexus of capillaries
• connects hypothalamus to pituitary
• circumventricular organ (no BBB)

Question 23

tuberoinfundibular tract

Answer 23

-collection of axons carrying releasing/inhibiting factors to the median eminence

Question 24

VMN

Answer 24

satiety center

lesion = insatiable appetite

Question 25

lateral nucleus

Answer 25

feeding center

lesion = anorexia

Question 26

leptin receptors are present on _________ nucleus

Answer 26

leptin receptors are present on ARCUATE nucleus

Question 27

mamillary bodies / dorsomedial thalamus

Answer 27

lesion = Korsakoff’s Syndrome

• confabulatory amnesia
• caused by alcohol, poor diet