Hypothalamus - Anatomy

Front 1

What are the 3 regions of the hypothalamus from medial to lateral? What are the 4 regions from anterior to posterior?

Back 1

periventricular zone, medial zone, lateral zone

preoptic, supraoptic (anterior), tuberal, mammillary

Front 2

What is the primary function of the periventricular zone?

Back 2

Maintains homeostatsis of the autonomic system - sensory and visceral motor via neurons that secrete hormones.

Front 3

What is the primary function of the medial zone?

To what two basic (outside) areas do its nuclei connect?

To what other hypothalamic areas does it connect?

Back 3

Regulation of motivated behaviors via large nuclei in this zone.

Limbic and brainstem areas

Nuclei connect with each other and project to nuclei in the periventricular zone.

Front 4

What is the function of the lateral zone in the hypothalamus?

What bundle goes through this region?

Back 4

An undifferentiated region that is involved in mediating arousal and sensory sensitization associcated with motivated behavior relating to reproduction.

Medial forebrain bundle

Front 5

What are the four main afferents of the hypothalamus?

Back 5

Fornix

Medial Forebrain Bundle

Amygdalo-hypothalamic fibers

Retinohypothalamic fibers

Front 6

What are four other sensory types of input to the hypothalamus?

Back 6

thermoreceptors

barroreceptors

osmoreceptors

steroid hormone receptors

Front 7

The fornix is arises from neurons in these two areas:

Back 7

subiculum and hippocampus

Front 8

List the two sets of hypothalamus afferents that come from the hippocampus.

What parts of the hypothalamus do each of these afferents connect?

Back 8

precommissural and postcommissural

precommissural => septum, preoptic area and anterior hypothalamus

postcommissural => mammillary N. and lateral hypothalamus

Front 9

Describe the medial forbrain bundle and where it tranverses through the hypothalamus.

It contains ascending and descending fibers that connect to what three areas in the brain?

Back 9

A diffuse band of fibers thar courses through the lateral hypothalamus zone.

Fibers connect to septum, hypothalamus and midbrain tegmentum.

Front 10

What are the retinohypothalamic fibers?

Back 10

Direct projection from retina to SCN or as collaterals of the retinogeniculate fibers

Front 11

What are the three major ascending efferents of the hypothalamus?

Back 11

Mammilothalamic

Hypothalamo-thalamic

Hypothalamo-amygdaloid

Front 12

List the four main descending efferents from the hypothalamus.

Back 12

Hypothalamo-spinal

Hypothalamo-medullary

Dorsal longitudinal fasciculus (PVN to central gray)

Mammillotegmental

Front 13

List the pathway for the mammillothalamic efferent.

Back 13

medial mammillary nuclei to anterior n. of the thalamus (part of the Papez circuit)

Front 14

List the pathway of the hypothalamo-thalamic efferent

Back 14

From lateral preoptic area to dorsomedial N. of thalamus

Front 15

List the pathway of the hypothalamo-amygdaloid efferent

Back 15

Reciprocal connections of amygdalohypothalamic fibers to dorsomedial amydgala

Front 16

List the pathway for the hypothalamo-spinal efferent

Back 16

Primarily from paraventricular N. of the hypothalamus (some fibers from the dorsomeidal and lateral hypothalamus). Terminate on neurons in the intermediolateral cell column (visceral efferents)

Front 17

List the pathway of the hypothalamo-meduallary efferent

Back 17

orginal from PVN, DMV and LH. Terminate in solitary nucleus, dorsal vagal motor n., n. ambiguus and nuceli of ventrolateral medualla (parasympthetic)

Front 18

List the pathway of the dorsal longitudinal fascisculus efferent

Back 18

from medial hypothalamic zones to PAG, reticular formation and dorsal vagal n. (preganglionic sympathetic and sacral parasympathetic)

Front 19

List the pathway of the mammillotegmental efferent

Back 19

Arises from medial mammillary nucleus. To dorsal and ventral tegmental nuclei in PAG, reticular formation, relay to autonomic nuclei in brainstem and spinal cord

Front 20

What are the names of the two neuroendocrine connections to the pituitary gland?

Back 20

tuberoinfundibular

hypothalamo-hypophysial

Front 21

Where do the tuberioinfundibular connections end? What do these terminals do in general terms?

Back 21

median eminence.

These terminals secrete releasing or inhibiting factors into the hypophyseal portal vasculature which travel to the anterior pituitary to regulate hormone secretion.

Front 22

What neurons are involved in the hypothalamo-hypophysial connections?

Where do these neurons project and what do they do?

Back 22

magnocellular neurons of the PVN and SON.

Axons travel directly to the posterior gland and release their hormone in general circulation.

Front 23

The anterior pituitary gland develops from what area?

Back 23

Develops as an outpocketing of the roof of the oral cavity known as Rathke's pouch.

Front 24

What are the five cell types of the anterior pituitary and what are the associated pituitary hormones?

Back 24

gondadotropes: Luteinizing H., Follicle Stimulating H.

lactotropes: Prolactin

thyrotopes: Thyroid Stimulating H.

corticotropes: AdrenoCoritcoTrophic H.

somatotropes: Growth H.

Front 25

What two hormones are released by the posterior pituitary gland?

Back 25

vasopressin (AVP) and oxytocin (OX)

Front 26

Where are the three primary locations of the cell bodies for GnRH?

Where are the primary terminals for the GnRH?

Back 26

Diagonal Band of Broca, OVLT, MPN (medial preoptic)

median eminence

Front 27

Where the the primary locations for the CRH cell bodies and terminals?

Back 27

PVN and median eminence

Front 28

Where are the primary locations for the cell bodys of the TRH and where are the terminals?

Back 28

Periventricular area, PVN

Meidan Eminence

Front 29

Where the the primary locations for the CRH cell bodies and terminals?

Back 29

PVN and median eminence

Front 30

Where are the cell bodies and termainsl for GHRH?

Back 30

arcuate N.

Median eminence

Front 31

Where is the primary location for cell bodies releasing somatostatin? Where are the terminals?

Back 31

PVN

median eminence; neurohypophysis/meidan emience

Front 32

Where are the cell bodies and terminals releasing Arginine Vasopressin?

Back 32

SON, PVN

nuerohypohysis, median emience

Front 33

Where are the cell bodies releasing oxytocin?

Back 33

PVN, SON

Front 34

What are the six required characteristics of a hypothalamic releasing or inhibiting hormone?

Back 34

1) Activity must be extractable from the while hypothalamus or median eminence

2) Concentration in portal blood must be greater than in the systemic ciruclation

3) Dynamics of secretion in portal blood must correlate with the dynamics of adenhypophysial hormone secretion

4) Extractered materail must be active in vivo and in vitro

5) Inhibitors of neurohormone must affect physiological endpoitns.

6) Target cells should have specific receptors for neurohormones.