Hypothalamus 2 Flashcards
The main pattern generator of thermogenesis is the _
N. raphe pallidus
Heat sensitive neurons in the _ inhibit the RPa (warm response)
medial preoptic area of anterior hypothalamus
Cold sensitive neurons in the _ activate the RPa (cold response)
Posterior hypothalamus
Medial Preoptic area (MPOA) uses _ neurotransmitter to inhibit _ and _ during the warm response via the _ nucleus
GABA
dorsomedial / posterior hypothalamus
RPa
paraventricular
Cool sensitive neurons are located in the _ and _. These excite _ in the cool response
Dorsomedial hypothalamus
Posterior Hypothalamus
RPa
Lesions affecting the anterior hypothalamus lead to _
Lesions affecting the posterior hypothalamus lead to _
hyperthermia
Matching ambient temperature
During fever, MPOA neurons contain _ receptors inhibited by _ made in capillary walls. This results in raising the set point
EP3
Prostaglandin E2
The major function of the suprachiasmatic nucleus (SCN) is as _
Endogenous circadian oscillator
The suprachiasmatic nucleus (SCN) receives inputs from the _ via the _ tract
Photosensitive retinal ganglion cells
retinohypothalamic
The suprachiasmatic nucleus (SCN) projects extensively throughout the hypothalamus, true or false
True
The pineal gland produces _. This production is inhibited by _
Melatonin
Light
Total melatonin _ with age
Decreases
Melatonin acts through the _ and _ receptors. These receptos inhibit insulin release, cortisol release
MT1 and MT2
_ disruption is implicated in jet lag, sleep disorder, SAD
Melatonin
The _ is active during sleep. It is reciprocally connected with the _, which contains histamine release
Ventrolateral preoptic nucleus
Tuberomamillary nucleus
the Tuberomamillary nucleus (histamine) innervates the _, which is involved with arousal, as well as the entire cortex
ascending reticular activating system
A switch between the _ and _ create a switch between wakefulness and sleep state
Ventrolateral preoptic nucleus
Tuberomamillary nucleus
The VLPO is inhibited by GABA from the _ as well as _ from the locus coerulus and _ from serotonin from the _
Tuberomamillary nucleus
NE
median raphe n.
Orexin neurons from the _ project to the _ (3) and maintain the “switch” in the awake position
Lateral hypothalamus
VLPO
TMN
ARAS
Patients with narcolepsy have reduced amounts of
orexin
Lesions of the anterior hypothalamus lead to _
Lesions of the posterior hypothalamus lead to _
Insomnia
Sleepiness
The major function of the _ is to generate appetite. This is done by _ containing neurons
Lateral hypothalamus
Orexin
Motivation for eating behavior is generated by LH projections to the _
Basal forebrain
The _ controls the LH via to competing output systems
Arcuate nucleus
The arcuate nucleus uses _ to inhibit feeding. It then uses _ to promote feeding
POMC (pro-opiomelanocortin)
NPY
POMC inhibits the LH by acting on _ receptors. Mutation of these receptors have been implicated in obesity
Melanocortin (MC4R)
NPY is able to block the actions of POMC on _ receptors, as well as directly inhibit _ neurons using GABA
Melanocortin (MC4R)
POMC
POMC and NPY project to the _ to control pituitary hormone release, autonomics and visceral afferents related to feeding
Paraventricular nucleus
Short term humoral signals are 2 fold.
_ (hunger hormone) is produced by _ and _. Its levels drop after an adequate meal. It is excitatory to NPY neurons
Ghrelin
Stomach
Pancreas
Short term humoral signals are 2 fold.
_ is made in the duodenum. It is excitatory to POMC, suppressing feeding
CCK
The long term feeding signals to the hypothalamus are _ (3)
Leptin - excites POMC
Insulin
Monoamines (NE and 5HT)
The major neuron regulating satiety is the _. It functions by activating _ neurons. The strength of these inputs diminish with feeding
Ventromedial nucleus
POMC
Lesions of the ventromedial nucleus result in _
Uncontrollable eating
LH lesions lead to _. Lesions to the medial hypothalamus lead to _
abolished eating
uncontrollable eating and drinking
Anorexia, forced starvation, has been associated with reduced levels of this “hunger hormone”
Ghrelin
Volumetric Thirst activate _ which in turn cause ADH release from the supraoptic and _ nucleus
MPOA
Paraventricular
Angiotensin II is detected by the _ of the hypothalamus, which in turn cause ADH release from the paraventricular and _ nucleus
subfornical organ
supraoptic
Osmotic thirst is detected by _, leading to increased salt appetite
VOLT - vascular organ of the lamina terminalis
Destruction of the anterior hypothalamus leads to _
Loss of drinking desire
The hypothalamus can directly modulate the baroreflex by acting on _
RVLM
The hypothalamus modulates reproductive milestones by acting on the _.
Anterior Pituitary
Onset of reproductive milestones depend on (3)
body mass
light cycles
Stress
Sexual behaviors are driven by projections of _ neurons of the Arcuate n. to the _
POMC
MPOA
Arcuate n. sends dopaminergic projections to the _ via the tubero-infundubular tract to inhibit _ release
median eminence
prolactin
Medial hypothalamus lesions lead to _ . Ventromedial hypothalamus lesions lead to _ and _
Curbed desires and paraphilias
Hunger and rage
High levels of circulating _ are associated with impotence and low libido
Prolactin
