Nucleotide Status in Erythrocytes of Rats Infected with Plasmodium Berghei

Abstract

Red blood cells (RBC) as well as plasmodia are not able to synthesize purines; therefore salvage pathways are essentiell for both. The source of purines is plasma adenosine. It enters the plasma membrane of erythrocytes via a specific transport protein which is located in band 4.5 together with the glucose transporter¹. The parasites provide a high influx of adenosine into their infected host by altering the expression of the nucleoside transporter. In the erythrocyte adenosine is converted to AMP and to hypoxanthine. Last compound is preferentially translocated into parasites. They are characterized by a high capacity of purine nucleotide metabolizing enzymes including those of the salvage pathways. Parasites use hypoxanthine as substrate for the synthesis of all purine nucleotides. The enzymes of these reactions are associated with the plasmodial membrane. Therefore the question arises which interactions do exist in the purine nucleotide metabolism between the two compartments parasite and red blood cell. Is was our aim to clarify it by an analysis of the purine nucleotide status.