Synergistic interaction of heavy metal salts with hyperthermia or ionizing radiation

Background: One of the ways to enhance the effectiveness of radiation therapy or sterilization of objects of various origins is to use chemical agents in combination with hyperthermia and ionizing radiation. Some drugs commonly used in medicine include heavy metals. However, the study of their synergistic interaction with other agents is fragmentary. The purpose of this study was to establish a general pattern of synergistic interaction of heavy metal salts with hyperthermia or ionizing radiation. Materials and Methods: Bacterial and diploid yeast cells were used in the experiments. To quantify the synergistic effect, cell survival was determined after individual effects of heavy metal salts, hyperthermia, ionizing radiation, and their simultaneous action. The following heavy metal salts were used: lead iodide, potassium dichromate, cisplatin, and zinc sulfate. Results: For all analyzed cases, optimal conditions of interacting agents were observed under which the greatest synergistic effect was achieved. Conclusion: Comparison of the results obtained with previously published data indicates general patterns of synergistic effect display that are independent of acting agents, biological objects, and tests.