exogenous pathway

• once chylomicrons reach the capillary beds in tissues, chylomicrons get to capillaries in tissue beds and will interact with the enzyme lipoprotein lipase
• lipoprotein lipase hydrolyzes triglycerides into glycerol and free fatty acids
• after hydrolyzation, Glycerol and fatty acids are taken up by cells and used for fuel 
• In some cases where glycerol and fatty acids are not used for fuel, they are re-esterified into triglycerides and stored, particularly in adipose sites
• Hormonal control of triglycerides - epinephrine and cortisol promote hydrolysis of triglycerides (aka lipolysis) 
• epinephrine and cortisol promote lipolysis
• insulin inhibits lipolysis
• an alternative way to synthesize triglycerides occur when glucose is cleaved into 2 three carbon sugars, at which point, three carbon molecules can be made into glycerol or by several reactions mediated by enzymes, first become pyruvate, then becomes acetyl co-enzyme
• after acetyl co-enzyme is created and if it does not enter Kreb's cycle, can then be converted into fatty acids by several enzymatic reactions
• Excessive production or conversion results in the formation of acetoacetyl-coenzyme A; then converted to one of 3 ketones
• acetoacetic acid [diacetic acid], acetone, B-hydroxybutyric acid are the three ketones that can result ine xcessive production of acetoacetyl-coenzyme A
• Some chylomicrons lose triglycerides, cholesterol, and proteins to HDL in circulation; at this point, become remnants; when remnants make it to the liver, they are broken down