Obesity Flashcards
which two hormones does the paraventricular nucleus in the hypothalamus secrete
CRH
TRH
which two areas of the hypothalamus are involved in the regulation of food intake
arcuate nucleus paraventricular nucleus (adjacent to 3rd ventricle)
cells are sensitive to blood glucose
in relation to appetite what is the function of the lateral region of the hypothalamus
stimulates hunger
lesion = decr. body weight
in relation to appetite what is the function of the ventromedial hypothalamus
promotes satiety
lesion = hyperphagia
what is leptin
adipostat
acts on arcuate nucleus
high levels -> anorexigenic peptides (CART, alpha MSH)
low levels -> orexigenic peptides (neuropeptide Y, Agouti related peptide)
in the majority of obese people there are high levels
what effect does insulin have on the hypothalamus
cause the production of anorexigenic peptides
levels may be elevated in obesity
where in the CNS does ghrelin act and what does it do
acts on arcuate nucleus
produced by stomach
levels rise before meals and sink after
levels are reduced in obesity
what effect does vagal nerve stimulation have on appetite
promotes satiety
activated by stomach distension and CCK
projects to the nucleus of the solitary tract
what happens to serotonin levels in the hypothalamus on anticipation of food
increases
5HT reuptake inhibitor promotes satiety
where is dopamine produced
ventral segmental area in response to rewards
what stimulates and inhibits the endocannaboid system
stimulated by fasting and ghrelin
inhibited by leptin
what are the peripherally acting appetite suppressing signals
peptide YY - produced by L cells in the large bowel - inhibit appetite stimulation
GLP-1 - co-secreted with pYY, inhibits feeding and enhances insulin secretion,
oxyntomodulin - produced by gut
what are the peripherally acting appetite stimulating signals
ghrelin - produced by oxyntic cells in fundus of stomach (stimulates growth hormone and increased food intake)
obestatin -
how would you calculate BMR
weight (KG) x 100kJ/day
or
kg x 24kcal/day
under what conditions and from where is neuropeptid Y released
released in response to low leptin and insulin, activated by ghrelin
released from neutrons that extend from the arcuate nucleus to PVN
stimulates food intake
co-secreted with AgRP
