MSH: An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.,CSP: adenine nucleotide containing three phosphate groups esterified to the sugar moiety; in addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.,NCI: A substance present in all living cells that provides energy for many metabolic processes and is involved in making RNA. Adenosine triphosphate made in the laboratory is being studied in patients with advanced solid tumors to see if it can decrease weight loss and improve muscle strength.,NCI: An adenine nucleotide comprised of three phosphate groups esterified to the sugar moiety, found in all living cells. Adenosine triphosphate is involved in energy production for metabolic processes and RNA synthesis. In addition, this substance acts as a neurotransmitter. In cancer studies, adenosine triphosphate is synthesized to examine its use to decr