3.13.14 29 Hypothalamus

Question 1

What connects to the limbic system and plays a major role in elaborating our MOST BASIC DESIRES for survival via efferent outflow to somatic and autonomic centers?

Answer 1

Hypothalamus

Question 2

What mnemonic summarizes all of the functions of the hypothalamus

Answer 2

Hypothalamus wears “TAN HATS to bed”

Thirst/water balance
Adenohypophysis
Neurohypophysis
---
Hunger
Autonomics
Temperature
Sexual urges
---
To bed = circadian rhythm

Question 3

What nuclei regulate temperature?

Answer 3

Posterior = heating = sympathetic (constriction of peripheral blood vessels, shivering; decreased sweating)

Question 4

What are the key AFFERENT pathways of the hypothalamus?

Answer 4

Dorsal longitudinal fasciculus
Stria terminalis
Fornix
Retina

Question 5

What are the key EFFERENT pathways of the hypothalamus?

Answer 5

Dorsal longitudinal fasciculus
Stria terminalis
Mammillothalamic tract
Hypophyseal portal system

Question 6

What connects the hypothalamus to and from the brainstem/spinal cord?

Answer 6

Dorsal longitudinal fasciculus

Question 7

What connects the amygdaloid complex to and from the hypothalamus?

Answer 7

Stria terminalis

Question 8

What connects the Hippocampal formation and septum to the hypothalamus? (Afferent only)

Answer 8

Fornix

Question 9

What connects the hypothalamus to the cortex and mammillary bodies?

Answer 9

Mammillothalamic tract

Question 10

How does the hypothalamus regulate the anterior pituitary?

Answer 10

Releasing and inhibitory hormones through the hypophyseal portal system

Question 11

Describe the symptoms and affected structures of amenorrhea

Answer 11

Arrest of menses
Insufficient LHRH or FSH
--
AH/POA
Tuberal hypothalamus
Pituitary

Question 12

Describe the symptoms and affected structures of galactorrhea

Answer 12

Excessive milk production
Prolactin and oxytocin
--
Arcuate nucleus
AH/POA
Median eminence
Pituitary stalk

Question 13

Describe the symptoms and affected structures of poikilothermia

Answer 13

Disregulation of temperature
--
PH (primarily)
or
PH and AH/POA

Question 14

Describe the symptoms and affected structures of diabetes insipidus

Answer 14

Polydipsia (thirst) and polyuria
--
Supraoptic nucleus
Paraventricular nucleus
Pituitary stalk

Question 15

Describe the association of hypothalamus pathology and visual signs

Answer 15

Tumors of the pituitary can compress the optic nerve and/or optic chiasm (usually bitemporal heminanopia)

Question 16

Describe the symptoms and affected structures of acromegaly

Answer 16

Adenohypophyseal lesions (ant. pituitary)
Arcuate nucleus
Periventricular region of hypothalamus

Question 17

Describe the symptoms and affected structures of Cushing’s disease

Answer 17

Hyperadrenocorticism (increased ACTH); usually pituitary adenoma
--
Hypertension
Weight gain (skin changes, striae); truncal obesity and buffalo hump
Moon facies
Hyperglycemia
Osteoporosis
Amenorrhea
Immune suppression
Muscle weakness

Question 18

Where to the autonomic projections of the hypothalamus end up?

Answer 18

Parasympathetics:
Brainstem (EW, S/I salivatory, dorsal motor)
Spinal cord (Parasympathetic nuclei - S2-4)
—
Sympathetics:
Spinal cord (IML - T1-L2)

Question 19

What nucleus is associated with temperature?

Answer 19

(Same as autonomics)
Cooling = anterior/preoptic area
Heating = posterior

Question 20

What nucleus is associated with adenohypophysis control?

Answer 20

Arcuate and paraventricular

Question 21

What nucleus is associated with neurohypophysis control?

Answer 21

Supraoptic and paraventricular

Question 22

What nucleus is associated with hunger/satiety?

Answer 22

Hunger = lateral
Satiety = ventromedial

Question 23

What nucleus is associated with autonomics?

Answer 23

(Same as temp control)
Parasympathetic = anterior/preoptic (cooling)
Sympathetic = posterior (heating)

Question 24

What nucleus is associated with thirst?

Answer 24

(Same as neurohypophysis control)

Supraoptic and paraventricular

Question 25

What nucleus is associated with sexual urges?

Answer 25

Anterior (the foremost thing on our minds)

Question 26

What nucleus is associated with circadian rhythm?

Answer 26

Suprachiasmatic