Histo Lecture 8

  1. What gives structure to adipose tissue?
    -Reticular tissue
  2. Adipose tissue is lowly or highly vascularized?
  3. Locations of Adipose tissue
    • -Subcutaneous areas
    • -Body cavities
    • -Surrounding organs and tissues (nerves, vessels)
  4. Functions of Adipose Tissue
    • -Reservoir for lipid storage
    • -Temperature insulation
  5. Describe uniocular fat
    • -"yellow fat"
    • -Most common type
    • -Single lipid droplet fills the majority of cellular cytoplasm
    • -Nucleus and cytoplasm are "squeezed" into the periphery of adipocytes
  6. Describe Multiocular fat
    • -"Brown fat"
    • -Infants and animals that hibernate
    • -Limited amount in adults
  7. Cytoplasm in multiocular fat contains:
    • -Numerous lipid droplets
    • -Many mitochondria
    • -Central nucleus
  8. How does multiocular fat produce heat?
    Thermogenin shunts energy away from ATP production in the transmembrane protein of mitochondria to produce heat instead
  9. How are lipids transported?
    • -Lipids are attached to proteins which allows them to become "soluble" in plasma and allows cells to control entry and exit of lipid molecules
    • -Vary in size (VLDL, LDL, HDL, IDL, chylomicrons)
  10. Describe chylomicrons
    • -Small particles (3μm in diameter) formed in the intestine and transported in plasma
    • -Triglycerides packaged with cholesterol, phospholipids and proteins
  11. Describe how lipids are acquired and stored
    • -Most fatty acids have origins in dietary fats
    • -During digestion, triglycerides are split into monoglycerides and fatty acids in the GI tract (transported as chylomicrons)
    • -Liver synthesizes components into triglycerides which are then transported in form of VLDL
    • -Liver can also convert glucose to fatty acids and glycerol
  12. What is the function of Lipoprotein lipase?
    • -Enzyme within endothelial cells of capillaries
    • -Breaks down lipoproteins and releases FFA (free fatty acids) and glycerol
  13. Triglycerides are stored in ______ within the cytoplasm
  14. This hormone stimulates the uptake of glucose and adipocyte synthesis:
  15. Lipids are mobilized from adipocytes in response to there two stimuli:
    • -Hormonal stimuli (growth hormone, thyroid hormone, cortisol)
    • -Neurogenis stimuli (norepinephrine)
  16. Functions of Hormone Sensitive Lipase (HSL)
    • -Becomes active when triglyceride release from adipocytes is stimulated
    • -HSL hydrolyzes trigs into FFAs and glycerol
    • -FFAs (bound to albumin) and glycerol diffuse into capillaries for distribution
  17. Hormones that activate HSL
    • Thyroid Hormone
    • Growth Hormone
    • Epinephrine/Norepinephrine
    • Cortisol
  18. In what order are fats mobilized?
    • -Fats in subcutaneous, mesenteric, and retroperitoneal areas are mobilized first
    • -Adipose tissue in hands, feet, and retro-orbital fat pads resist long periods of starvation
  19. Functino of Leptin
    • -Protein produced by adipocytes
    • -Regulates metabolism, energy intake and production
    • -Acts on hypothalamus to decrease food intake and increase energy utilization
  20. 5 Types of anthropomety
    • -DEXA
    • -Bod Pod
    • -Underwater weighing
    • -Electrical impedance
    • -Skin calipers
  21. Types of Obesity
    • -Exogenous - caloric intake > caloric expenditure
    • -Endogenous - metabolic cause (<1% of all cases)
  22. Incidence of Obesity
    • -64% of Americans are overweight
    • -30% of Americans are obese
    • -15% of American children are obese (ages 6-17)
    • -Most at risk: Minorities, low income, lower education
  23. Name some consequences of Obesity
    • -Hypertension
    • -Coronary artery disease
    • -Dyslipidemia
    • -Stroke
    • -Type II diabetes
    • -Gall bladder disease
    • -Osteoarthritis (OA)
    • -Sleep apnea
    • -Cancer
  24. How do chronically trained muscles increase use of lipids?
    • -Increase capillary/muscle fiber ratio
    • -Increase # of mitochondria
    • -Increase in oxidative enzymes which allow for icnreased aerobic capacity
Card Set
Histo Lecture 8
Adipose Tissue