l basic neuroscience lecture 13

8/16/2019 l Basic Neuroscience Lecture 13

1/17

Basic Neuroscience: NeuroanatomyDr. Bodnar: Lecture 13The Hypothalamus


2/17

Hypothalamic Borders

• Caudal: Mammillary Bodies

• Rostral: Pre-Optic Area (MPOA/LPOA)

• Medial: III e!tricle

• Lateral: I!ter!al Capsule• "orsal: #o!a I!certa$ %halamus

• e!tral: Hypothalamo-Hypophysial Portal &ystem a!dPituitary 'la!d


3/17

Perie!tricular Hypothalamic

uclei• *pe!dyma o+ III e!tricle, "L e.ere!t

• Paricellular !eurosecretory system


4/17

Perie!tricular Hypothalamus

Interactions between somatostatin (SRIH)-producing neurons in the hypothalamic

periventricular nucleus (Pev) and growth hormone releasing hormone (GHRH)-

producing neurons in the arcuate nucleus with both reciprocal proections to each

other and to the e!ternal "one o# the median eminence$ Ghrelin (GHR) may also

in#luence GH secretion by acting directly on somatotrophs or through stimulatory

e##ects on GHRH neurons$ %P & anterior pituitary' GH & growth hormone' IG &

insulin-lie growth #actor' *+ & median eminence' PP & posterior pituitary$ R-SRIH

and R-GHRH correspond to receptors #or the respective peptides$


5/17

Pre-Optic Hypothalamic uclei

• Pre-Optic uclei

%raersed y medial +orerai! u!dle

Re0ulatio! o+ heat dissipatio!

Re0ulatio! o+ se1 hormo!es• &upra-Chiasmatic ucleus

"iur!al a!d polyphasic rhythmicity +or sleep$ +eedi!0$dri!2i!0 a!d locomotio!


6/17

Pre-Optic Hypothalamic uclei

Se!ual di##erentiation o# the nervous system occurs between males and #emales' such as Spinal

,ucleus ulbocavernosus (S,) in the male spinal cord or the enlarged Se!ual .imorphic ,ucleus

(S.,) in the male hypothalamus$ /he *edial Preoptic area (*P%)' %mygdala (%*G)' and asal

,ucleus o# the Striatum /erminalis (b,S/) are critical #or male se!ual behavior$ /hese brain areas are /-

sensitive$ emale se!ual behavior (e$g$' lordosis behavior) is regulated in part by the 0entromedialhypothalamus (0*H) and the %*G$


7/17

&uprachiasmatic ucleus

/he tiny suprachiasmatic nucleus (S1,) o# the hypothalamus plays a central role in the daily

programming o# organismic #unctions by regulating day-to-day oscillations o# the internal milieuand synchroni"ing them to the changing cycles o# day and night and o# body state$ /his

biological cloc drives the daily e!pression o# vital homeostatic #unctions as diverse as #eeding'

drining' body temperature' and neurohormone secretion$ It adaptively organi"es these body

#unctions into near-23-hour oscillations termed circadian rhythms$ /he S1, imposes temporal

order 4) through generating output signals that relay time-o#-day in#ormation' and 2) through

gating its own sensitivity to incoming signals that adust cloc timing$


8/17

&upra-Optic a!d Parae!tricularuclei

Parocellular (%eal)$ Ma0!ocellular (Purple)


9/17

Medial/Arcuate Hypothalamus


10/17

Mamillary Bodies

*aor Inputs and 5utputs6 orni! and *amillo-/halamic /racts

ehavioral +##ects6 Punishment ehavior


11/17

Mamillo-%halamic %ract a!dor!i1


12/17

Lateral Hypothalamus


13/17

Hypothalamic A00ressio!

MedialHypothalamus

A.ectieA00ressio!

LateralHypothalamus

PredatoryA00ressio!


14/17

&tress Respo!ses


15/17

Adre!o-Corticotrophic &ystem


16/17

&ympatho-Medullary &ystem


17/17

Adreno-Cortico and Sympatho-edullary!nteractions

l basic neuroscience lecture 13

Documents