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7.3: Extrahepatic Macronutrient and Alcohol Metabolism

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    Because the liver is so important in metabolism, the term extrahepatic has been defined to mean "located or occurring outside of the liver1". We are next going to consider extrahepatic tissue metabolism.

    Figure 7.31.png

    Figure 7.31 The liver "is kind of a big deal2"

    To start considering the metabolic capabilities of the extrahepatic tissues, we start by removing pathways that only or mostly occur in the liver:

    • Alcohol oxidation
    • Gluconeogenesis
    • Ketone body synthesis
    • Urea synthesis
    • Lactate breakdown
    • Glucose-6-phosphatase

    These metabolic processes are crossed off in the figure below.

    Figure 7.32.png

    Figure 7.32 Removing the pathways that only or mostly occur in the liver3

    We are left with metabolic capabilities that are listed and shown below.

    • Glycogen synthesis and breakdown
    • Glycolysis
    • Fatty acid synthesis and breakdown
    • Triglyceride synthesis and breakdown
    • Protein synthesis and breakdown


    Figure 7.33 The metabolic capability of the extrahepatic tissues3

    We will use this figure as the base for metabolic capabilities of the different extrahepatic tissues to compare what pathways other tissues can perform versus all the pathways performed by extrahepatic tissues. In an effort to keep this simple, we are going to focus on four extrahepatic tissues in the following subsections:

    References & Links


    This page titled 7.3: Extrahepatic Macronutrient and Alcohol Metabolism is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Brian Lindshield via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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