Hyp-Functions Flashcards
Hypothalamus - Functions
Posterior Nucleus; function & loc
Sympathetic output (fight or flight) Thermogenesis
(posterior region)
Hypothalamus - Functions
Tuberomammillary nucleus; function & loc
Histamine sys - Promoting Wakefullness
posterior region
Hypothalamus - Functions
Fornix
memory consolidation
projects from hippocampus to mammillary bodies
(Posterior region of hypothalamus)
Hypothalamus - Functions
Mammillary body; function
memory consolidation
posterior region
Hypothalamus - Functions
Lateral Hypothalamus; function
feeding center
orexin sys - promoting wakefulness & appetite
(posterior region)
Hypothalamus - Functions
Posterior Region - consists of;
Posterior nucleus
Tuberomammillary nuc
Mammillary body
Lateral hypothalamus
Hypothalamus - Functions
Tuberal Region - consists of;
Lateral Hypothalamus
Ventromedial nuc
Arcuate nuc
Dorsomedial nuc
Hypothalamus - Functions
Ventromedial nuc; function
satiety center
contains leptin-sensitive neurons
(tuberal region)
Hypothalamus - Functions
leptin
increase conc in ventromedial nuc -> cessation of eating
Hypothalamus - Functions
Dorsomedial nuc; function
feeding & body weight regulatio
nmay serve as relay center of energy homeostasis
lesion: feeding & body wt dysfunction
(tuberal region)
Hypothalamus - Functions
Arcuate nuclesu; function
Secretion of hypophyseal hormones Feeding behavior (orexigenic & anoretic neurons)
(tuberal region)
Hypothalamus - Functions
Dorsomedial nucleus; function
control feeding & body wt
tuberal region
Hypothalamus - Functions
Anterior supraoptic region; consists of
Anterior nuc Suprachiasmatic nuc Supraoptic nuc Paraventricular nuc Lateral hypothalamus
Hypothalamus - Functions
Anterior nuc; function
control of Parasymp
Thermoregulation (dissapation of heat)
(ant supraoptic region)
Hypothalamus - Functions
Suprachiasmatic nuc; function
Circadian rhythms (bio clock & modulates pineal gland function)
(ant supraoptic region)
Hypothalamus - Functions
how does the suprachiasmatic nuc control circadian rhythms?
receives light info from retinal ganglion cellsvia; Retinohypothalamic tract
info relayed via desc symp fibers from hypothal -> intermediolat nuc -> sup cervical ganglia -> pineal gland
Inhibits prod of Melatonin during day
(melatonin = sleep-promoting hormone)
Hypothalamus - Functions
Paraventricular nuc; function
water retention (vasopressin secreting) milk letdown, uterine contraction (oxytocin secreting) control ant pituitary function (ACTH, TSH)
(ant supraoptic region)
Hypothalamus - Functions
milk letdown & water retention
paraventricular nuc
magnocellular neurosec neurons project to Posterior Pituitary;release Oxytocin or Vasporessin (ADH) in to general circulation
Vasopressin - inc water perm in collecting duct, activated by inc in osmolarity, circ levels of angiotensin, dec BP, hypovolemia
Oxytocin - stim of nipple -spinal pathways->hypothalamus = act of these neurons -> Oxytocin release => contraction of myoepithelial cells
Hypothalamus - Functions
paraventricular nuc; control of Ant Pituitary function
parvocellular neurosec neurons project to the median eminence/portal sys to control ant pituitary function;
Corticotropin-RH N - enhance adrenocorticotropic hormone (ACTH)
Thyrotropin-RH N - enhance thyroid-stimulating hormone (TSH) release
Somatostatin-R N - inhibit growth hormone secretion
Hypothalamus - Functions
Supraoptic nuc; function
water retention
milk letdown, uterine mm contraction
(ant supraoptic region)
Hypothalamus - Functions
Supraoptic nuc - how it works
paraventricular nucmagnocellular neurosec neurons project to Posterior Pituitary;release Oxytocin or Vasporessin (ADH) to general circulation-
Just like the Paraventricular nuc
(except doesn’t alter secretions of ACTH, TSH, or GH)
Hypothalamus - Functions
Anterior Preoptic region; consists of
lateral preoptic nuc
medial preoptic nuc
of telencephalic orgiin, but functionally associated w/ hypothalamus
*only part that the lateral hypothalamus isn’t present
Hypothalamus - Functions
nucleus basalis of Meyner
rich in cholinergic neurons w/ wide projections to neocortex
compromised in Alzheimer disease
located laterally to the Lateral preoptic nuc - the Substancia Inominata
(in the Ant preoptic region)
Hypothalamus - Functions
Lateral preoptic nuc; function
Inhibits wakefulness
promotes non-REM sleep
(ant preoptic region)
Hypothalamus - Functions
Medial preoptic nuc; function
thermoregulation set point
release of gonadotrophic hormones (into med eminence) & sexual behavior
(ant preoptic region)
Hypothalamus - Functions
Stria terminalis
connects reciprocally the hypothalamus and amygdala
Hypothalamus - Functions
hypothalamic-hypophyseal portal system
system where factors controlling the hormonal secretion of the Anterior Pituitary gland are released and reach their target via a portal venous system
Hypothalamus - Functions
supraoptico-hypophyseal tract
contains axons from the paraventricular and supraoptic nuclei projecting to the posterior pituitary gland
Hypothalamus - Functions
retinohypothalamic tract
carries light info from retinal ganglion cells to the Suprachiasmatic nuc
Hypothalamus - Functions
dorsal longitudinal fasiculus
- contains afferent hypothalamic fibers - carring visceral and tast sens; relayed to the hypoth via the solitary and parabrachial nuc
2 contains efferent hypoth fibers innervating; preganglionic parasym neurons, pregang symp neurons in spinal cord, autonomic reg centers in medulla, periaqueductal gray (pain modulation)
Hypothalamus - Functions
hypophyseal portal system links;
the hypothalamus and pituitary gland
allows endocrine signalling between the two structures
Hypothalamus - Functions
arteris of pituitary gland
superior and inferior hypophyseal arteries
Hypothalamus - Functions
superior hypophyseal artery
forms a capillary plexus, primary portal plexus, that penetrates the median eminence and infundibulum
primary portal plexus drains via long portal veins to the secondary portal plexus in the ant pituitary
Hypothalamus - Functions
inferior hypophyseal artery
forms capillary network within the posterior pituitary
venous drainage via hypophyseal veins
Hypothalamus - Functions
nuclei of Neuroendocrin control
paraventricular
supraoptic
arcuate
medial preoptic
Hypothalamus - Functions
nuclei of Weight Control, Feeding, Drinking
ventromedial
lateral hyp
arcuate
dorsomedial
Hypothalamus - Functions
nuclei of Temp Reg and Fever
medial preoptic (thermoreg)
posterior (symp)
anterior (parasymp)
Hypothalamus - Functions
nuclei of Osmoreg, Water Balance, BP, B volume
posterior (symp) anterior (parasymp) paraventricular supraoptic CVO's
Hypothalamus - Functions
nuclei of Reproductive function
paraventricular (oxytocin)
supraoptic (oxytocin)
medial preoptic (inc LH and FSH)
Hypothalamus - Functions
nuclei of Sleep/Wake cycle
suprachiasmatic (circadian)
tuberomammillary (histamine-wakefullness)
ventrolateral preoptic nuc (non-REM sleep)
