W2: Blook Supply, Telencephalon, Diencephalon

Question 1

What protects the CNS?

Answer 1

Blood brain barrier

Question 2

Blood brain barrier

Answer 2

Location: surrounding the CNS
Made of: endothelial cells that are NOT fenestrated but have tight junctions.
Function: To protect the CNS (no bacteria, toxins, proteins, blood cells are transported)

Question 3

Fenestrated

Answer 3

to have pores

Question 4

What two major arteries supply the brain with blood?

Answer 4

1) Internal carotid artery

2) Vertebral/basilar arteries

Question 5

Internal carotid artery

Answer 5

supplies blood to eyes, anterior/middle cerebral artery and mid sagittal.

Question 6

Middle cerebral artery

Answer 6

(most important)

supplies majority of lateral surface of brain and 2/3 of temporal lobe (on the lateral side)

Question 7

Vertebral/basilar artiries

Answer 7

Branches off aorta, assends to lateral part of vertebrae to skull to foramen magnum and ends in the posterior cerebral artery.

Question 8

Posterior cerebral artery

Answer 8

Comes from verebral artery

Supplies occipital lobe and inferior side of temporal lobe.

Question 9

What arteries make up the Circle of Willis?

Answer 9

1) Anterior communicating artery
2) Anterior cerebral artery
3) Internal chorotid artery
4) Middle cerebral artery
5) Posterior cerebral artery
6) Basilar artery
7) Posterier communicating artery

Question 10

Anterior cerebral artery

Answer 10

connects the hemisphere

Question 11

Stroke

Answer 11

Caused by circulatory problems in the CNS and can lead to a loss of cortical function.

Question 12

Hemiplegia

Answer 12

Blockage of entire middle cerebral artery

Question 13

TPA

Answer 13

Tissue plasminigen activator
Dissolves clot if administered within 3-6hrs.
Cannot administer if bleeding

Question 14

Symptoms of there is a black in the posterior cerebral artery

Answer 14

Visual deficit

Learning/memory

Question 15

Where do the superior and inferior sagittal sinuses and straight sinus drain to?

Answer 15

They drain posteriorly into the transverse sinuses and then the sigmoid sinuses.

Question 16

How does venous blood and CSF exit the skull? How does it return to circulation?

Answer 16

Exit: internal jugular

Re-enter: superior vena cava

Question 17

Basal Ganglia

Answer 17

Location: Telencephalon
Made of: caudate, putamen, globus pallidus
Function: integrates motor & sensory information & initiates voluntary movement

Question 18

Corpus Striatum

Answer 18

Caudate

Putamen

Question 19

Afferent axons of the caudate-putamen make up what regions?

Answer 19

1) Corticostriate
2) Thalamostriate
3) Nigrostriate

Question 20

Where do the Corticostriate, Thalamostriate, Nigrostriate project from?

Answer 20

1) Corticostriate - from all parts of the cerebral cortex
2) Thalamostriate - from the thalamus
3) Nigrostriate - from the substantia nigra

Question 21

How are afferent axons organized?

Answer 21

somatotopically

Question 22

Parkinson’s Disease

Answer 22

A degenerative disease of the basal ganglia that produces movement disorders. Involves loss of cell bodies in substanita nigra that project azons to the casudate-putamen and use dopamine for neurotransmission. Treatment for Parkinson’s patients is to give them L-DOPA, which crosses the blood brain barrier and is converted to dopamine by DOPA decarboxylase.
Symptoms: slow motor function, trouble initiating motor function, resting tremor

Question 23

Basal ganglia motor command curcuit

Answer 23

Motor/somatosensory neurons of cerebral cortex > putamen > globus pallidus > ventral lateral thalamus > back to motor areas of cortex and facilitate cortical output.

Question 24

Huntington’s Disease

Answer 24

A rare autosomal dominant genetic disease causing degeneration of GABAergic neurons in the causdate-putamen and produces severe motor disorders. Currently there are no treatments but have located the gene, so effective genetic screening and couseling is available.
Symptoms: hyperactive/involuntary movement, severe change in cognition and personality.

Question 25

Thalamus

Answer 25

Relay station from sensory information (except olfaction) before it is transmitted to the cortex.

Question 26

What parts of the thalamus are responsible for different types of information relay?

Answer 26

1) ventral posterior lateral - somatosensory relay
2) lateral geniculate - visual relay
3) medial geniculate - auditory relay
4) ventral lateral nucleus - motor relay

Question 27

Hypothalamus

Answer 27

Location:
Made of: a large number of nuclei
Function: controls many aspects of homeostasis, controls the autonomic nervous system (ANS), regulation of body temperature, regulation of hunger and thirst. It secretes hormones (releasing factors) that control the pituitary gland.

Question 28

How do releasing factors move from the hypothalamus to the pituitary gland?

Answer 28

Releasing factors enter a capillary plexus in the hypothalamus and travel directly to the anterior pituitary via the portal vein.

Question 29

Anterior Pituitary

Answer 29

Glandular tissue that releases hormones into the blood stream in response to hypothalamic releasing factors.

Question 30

Posterior Pituitary

Answer 30

Neural tissue. Neurons in hypothalamus project axons into the posterior pituitary and release their hormone/peptides in the blood stream of the posterior pituitary.

Question 31

What are the hormones/peptides of the posterior pituitary?

Answer 31

oxytocin

antidiuretic hormone/vasopressin