<prompt> During vigorous strenuous exercise, which of the following amino acid is liberated from the skeletal muscles in maximum amount into circulationGlutamateGlutamineBranched chain amino acidsAlanine  <response>: Answer: d AlanineALANINE Alanine is a non-essential glucogenic amino acid. Alanine can be formed by transamination of pyruvate. The enzyme is alanine amino transferase ALT. Pyruvate Glutamate - Alanine alpha ketoglutarate This reaction requires pyridoxal phosphate PLP. Under conditions of starvation, the glucose alanine cycle is of special metabolic significance. Alanine is quantitatively the most important amino acid taken up by the liver from peripheral tissues, particularly from skeletal muscle. It forms a major participant in inter-organ transport of nitrogen Glucose-Alanine Cycle Cahill Cycle Alanine is transported to liver, transaminated to pyruvate and converted to glucose. This glucose may again enter the glycolytic pathway to form pyruvate, which in turn, can be transaminated to alanine. Glucose-alanine cycle is important in conditions of starvation. Thus net transfer of amino acid nitrogen from muscle to liver and corresponding transfer of glucose energy from liver to muscle is effected. Alanine cycle is intimately related with Coris cycleAmino AcidArterial Concentration Rest240 min Exercise mmoll Glycine188160Alanine192233Leucine126151!Valine242243Isoleucine6081! 