appetite hormonal 2
what is the difference between hunger and appetite
Hunger is the need to eat, appetite is the desire to eat
leptin inhibits what
NPY/AgRP neurons
What is gherlin?
a protein produced by the stomach cells that enhances appetite and decreases energy expenditure
what is the visceromotor response
adjustment of the balance of the sympathetic and parasympathetic divisions of the ANS
what does destroying LH do
animal has no interest eating
the PVN is
anorexigenic
several groups within the PVN have what function
anorexigenic, not eating
what can orexin regulate
appetite sleep/wakefulness arousal emotional memory reward/motivation stress
most mammals are born with a preference for sweet and salty tastes and with an a aversion to
bitter tastes
what happened in the db db and wildtype mouse
dbdb no change wild type food intake decreases eventually causing starvation decrease body weight experiencing twice the amt of leptin db db mouse produces a blood borne factor but does not respond to it wildtype mouse responds to factor and starves
the peak of satiety means what for food consumption
decrease
stimulating the VMH does what
depresses hunger
CCK is released by the ____ and ____ hunger
digestive tract, decreases
PYY is released by the ____ and ____ hunger
digestive tract, decreases
what are the results of the ob ob mouse
does not produce the blood borne factor that decreased food intake kept eating and had leptin deficency
destroying the VMH leads to what
eat excessively
true or false: leptin itself determines obesity
false
true or false: there is a single region in the brain that regulates appetite
false
leptin is released by the ____ and ____ hunger
fat cells (adipocytes) , decreases
what functions does arcuate nucleus function
feeding metabolism fertility cardiovascular regulation
what is satiety
feeling of fullness
treating humans w ghrelin increases what
feelings of hunger/appetite as well as food intake
what are some emotional influences on eating
food related sensory inputs, negative emotions
What are satiety signals?
hormones from the gut send signals to the hypothalamus to indicate fullness and satisfaction and slow feeding
ghrelin aka
hunger hormone
hormones released from the gut are sent to the
hypothalamus to indicate hunger
leptin acts on receptors in the
hypothalamus, VTA, hippocampus
orexin is released by the ____ and ____ hunger
hypothalamus, increase
What is the somatic motor response
incitement/motivation of an appropriate somatic motor response
gherlin is _____ during fasting and ____ after a meal
increased, decreased
what does stimulating LH do
induces appetite and food intake
PYY has what effect on NPY/AgRP neurons
inhibitory
the brain integrates what in regulation of feeding
insulin and blood glucose
what are the results of the db db mouse
lacks a functional receptor for this factor so cannot respond to leptin even if present
stimulating the PVN does what
leads to satiety and reduces feeding behavior
what is conditioned taste aversion
learning to avoid any taste that is followed by illness
what is conditioned taste preference
learning to prefer tastes that improve health
some obese patients have high leptin serum what does this mean
leptin resistance despite high levels of leptin food intake is not decreased so energy expenditure is not high
fat cells produce what
leptin, secrete into bloodstream
how is orexin stimulated
low blood glucose levels stimulate LH to produce it
what to POMC/CART neurons do
make proopiomelanocortin derived alpha melanocyte stimulating hormone and cocaine and amphetamine related transcript inhibit appetite, raise metabolism, and promote weight loss
hypothalamus is important in regulating
metabolic rate food intake body weight
NPY/AgRP neurons makes what
neuropeptide Y and agouti related peptide
destroying LH leads to
no interest in eating
what happened with ob ob and wildtype mouse
ob ob food intake and body weight went down wildtype no change bc ob ob responded to blood borne factor in wildtype but the ob ob mouse does not produce the factor to suppress the wildtype appetite
leptin deficiency leads to
obesity rat is hyperphagic (overeats)
what happens with ghrelin disruption in patients with disordered eating
obsess individuals have low baseline levels and poor regulation of ghrelin levels, levels do no drop after a meal so no signal for "just ate a meal"
the lateral hypothalamus is
orexigenic
what is released in the LH
orexin
insulin is released by the ____ and ____ hunger
pancreas, increases
what are some cognitive emotional influences on eating
sensory and memory
leptin, PYY and CCK do what
signal satiety
What do NPY/AgRP neurons do?
stimulate appetite, lower metabolism, promote weight gains
treating rats with ghrelin does what
stimulates food intake and growth hormone release
what is the humoral response
stimulation or inhibition of the release of piturairy hormones into the blood stream
receptors where monitor BGL
stomach liver and intestines
ghrelin is released by the ____ and ____ hunger
stomach, increase
What is a parabiosis experiment?
surgical union of two animals to link their blood and bb factors
after VMH or LH lesions what happens
there is a "new normal " at which body weight stabilizes
some obese patients have mutant leptin receptors (truncated) what does this mean
these patients cannot sense leptin they have a high leptin serum leptin treatment not effective because receptor has no effect
in patients with congenital leptin defieceincy what happens
they have no leptin but they have the receptors so treatment normalizes
how do different neurons mediate functions in the arcurate nucleus
througj specific neuropeptides
What are orexigenic signals?
to eat
true or false: NPY/AgRP neurons and POMC/CART neurons can regulate each other in the arcurate nuclues
true
true or false: leptins effects on the arcurate nucleus are long lasting
true
true or false: orexin and hypocretin are released in multiple areas
true
What is the lipostatic theory?
Eating is controlled by a hypothetical body- fat set-point (Long term homeostatic maintenance)
what are the major hypothalamic nuclei involved in appetite/feeding
LH VMH ARCURATE nucleus and PVN
in conditioned taste aversion the ____ produces the nausea while the ___ was the control
LiCl, NaCl
what is one way the PVN can be activated
POMC cells from the arcurate nucleus
leptin activates what
POMC/CART neurons
cells from the arcuate nuclues innervate what else
PVN, LH