Аннотация:This communication is devoted to the investigation of the complexes of 65Zn and conjugates of azacrown ethers, bearing four and six heteroatoms in the macrocycle, with a tetrapeptide-a somatostatin analog. The conditions for binding of the radionuclide and stability of the resulting complexes in the presence of serum proteins are studied. The data on the distribution in a healthy mouse and in vivo stability of complex ZnDOTA-P are presented.