ENDO 111 Obesity Flashcards
What BMI defines obesity?
30kg/m^2
What BMI defines morbid obesity?
40kg/m^2
What is metabolic syndrome?
Central obesity measured by waist circumference with 2 or more of:
increased [blood TG]
decreased [blood HDL] / increased [LDL]
Increased BP and blood glucose
What does Leptin do?
triggers production of active peptide in the hypothalamus that controls hunger and metabolism - burn calories
What does Ghrelin do?
stimulates appetite
What are the major fuels n the body and where do they arise from?
Glucose and Lactate from carbohydrate/ carb metabolism
FA’s and ketone bodies from fat/FA metabolism
Amino acids from protein
What tissues use fatty acids as a fuel?
Liver, Kidney cortex, cardiac muscle and skeletal muscle
What tissues depend on glucose as a fuel?
RBC, lymphocytes, brain and skeletal muscle
What tissues use ketone bodies?
Cardiac muscles, kidney cortex, skeletal muscle and brain in starvation
What factors raise a persons basal metabolic rate?
hyperthyroidism, cold exposure, regular exercise, disease and fever
What factors lower a persons basal metabolic rate?
hypothyroidism, dieting/starvation, being idle, hypothermia
What does a lesion of the ventromedial hypothalamus produce?
Hyperphagia
What does a lesion in the lateral hypothalamus result in?
decrease in body weight
How does the hypothalamus sense your weight?
Leptin ( an adipostat) produce by fat - more fat = more leptin
Where does leptin act primarily?
In the arcuate nucleus of the hypothalamus
What are the anorexigenic peptides?
CART and alpha-MSH
What stimulates production of anorexigenic peptides?
high leptin levels
What are the orexigenic peptides?
NPY and AgRP
What stimulates the production of orexigenic peptides?
Low leptin levels
What is the action of anorexigenic peptides?
Inhibit feeding behaviour
What is the action of orexigenic peptides?
activate feeding behaviour
What peptides bind to the MC4R receptor and what is their action?
Alpha MSH - activates it
AgRP - blocks it
Where does ghrelin act?
arcutate nucleus
What causes the feeling of satiety?
vagus nerve stimulation by stomach distension and CCK
