WAYS OF NEUTRALIZING AMMONIA IN THE HUMAN BODY, URINARY SYNTHESIS. ORNITHINE CYCLE

Ayyubova Sevinch Murodjon kizi; Hakimova Fayyoza Jahongir kizi; Mukhamedova Sevara Nigmatulla kizi

doi:10.5281/zenodo.11094551

Ayyubova Sevinch Murodjon kizi, Hakimova Fayyoza Jahongir kizi, Mukhamedova Sevara Nigmatulla kizi

Abstract. Ammonia is a key metabolite derived from amino acid metabolism and breakdown of nitrogenous substances in the gut,1,2 and present hypotheses suggest that it is of central importance in the pathogenesis of hepatic encephalopathy. Current therapeutic strategies are directed towards reducing circulating concentrations of ammonia. The two main pathways of ammonia detoxification are synthesis of urea and glutamine. In the physiological state, the liver is central in urea synthesis and this forms the basis of ammonia removal.3 The other organs capable of metabolising ammonia are the brain and skeletal muscle through synthesis of glutamine. In the presence of liver disease however, loss of functional liver mass and portocaval shunting may contribute to increased ammonia levels in plasma, thus predisposing to hepatic encephalopathy. In cirrhotic patients, skeletal muscles play an important role in the detoxification of ammonia to glutamine.4 Glutamine synthesis is however only a temporary method of ammonia detoxification. To remove ammonia from the body in a situation when urea synthesis is compromised (as happens in liver disease) requires transport of glutamine to the kidney, where it is metabolised to release ammonia, which is then excreted in urine.

Keywords: ammonia, metabolism, transport of glutamine, liver, kidney, neurohormones, ATP, Urea Cycle

References:

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