Analysis of the composition of peptides formed inside human erythrocytes and released by erythrocyte primary culture was carried out. The patterns of generation of relatively long (containing more than 28 amino acid residues) hemoglobin fragments inside the erythrocytes were established. The intraerythrocyte proteolysis is followed by the next degradation step coupled with excretion of newly formed shorter peptides from red blood cells. Both, the primary and the secondary proteolysis products are subjected in animal tissues to fkrther stepwise C-and N-terminal chain shortening, giving rise to families of closely related peptides. Amino acid sequences of hemoglobin fragments secreted by the erythrocytes were established. Most of these peptides were related to seven families grouped according to the patterns of proteolytic splitting of globin chains, Eight of the peptides released by erythrocytes showed biological activity in various tests systems, while the other overlapped with well-known biologically active hemoglobin fragments. On the basis of the presented facts a concept of "tissue specific peptide pool" describing a novel system of peptidergic regulation, complementary to the conventional hormonal and nervous systems was formulated

No abstract

No abstract