Page 101 - Biochemistry2 (08PB403)
P. 101

2- Pyruvate:

• Pyruvate, generated in muscle and other peripheral
   tissues, can be transaminated to alanine which is returned
   to the liver for gluconeogenesis.

• This pathway is termed the glucose-alanine cycle. Although
   the majority of amino acids are degraded in the liver some
   are deaminated in muscle.

• The glucose-alanine cycle is, therefore, an indirect
   mechanism for muscle to eliminate nitrogen while
   replenishing its energy supply.

• Within the liver the alanine is converted back to pyruvate
   and used as a gluconeogenic substrate or oxidized in the
   TCA cycle. The amino nitrogen is converted to urea in the
   urea cycle and excreted by the kidneys.

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