can someone tell me if this is right? ketogenesis question I'

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Fungi121

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So during prolonged starvation or diabetic ketoacidosis, you have low oxaloacetate because its being used for gluconeogenesis. Thus, you have a bunch of acetylcoa sitting around, so you make ketones instead. This ketogenesis occurs in the liver. During times of high energy requirements (or prolonged starvation or whatever), you have to break down fat, which gives you acetyl CoA (and NADH and FADH).

Is the liver basically like, "Sorry guys I would give you glucose buuuuut I'm running out of oxaloacetate and I have all this acetylCoA so here have ketones instead"?

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Yes, but I like to think of it more as "Give me glucose or I'm going to keep f*cking you up with all these excess ketones".. Since the liver is a jerk.
 
During starvation, gluconeogenesis is the primary source of glucose and it indeed utilizes OAA as a substrate. During PROLONGED starvation, ketones are synthesized because the brain recognizes there is a deficit and switches to using ketones (and still a bit of glucose) so that rbcs can utilize what little glucose is being made (rbcs can only use glucose but the brain can use ketones and rbcs). Some organs such as the heart and kidney love ketones and pick them up as they are made. Pretty much, the liver is the workforce for any starvation state. But the brain is smart and knows you have been starving for too long so it switches to using ketones as the liver continues primarily ketogenesis and still a bit of gluconeogenesis.
 
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