title: The polycation diethylaminoethyl dextran potentiates thermal cell killing.
abstract: The polycation diethylaminoethyl dextran (DEAE-dextran) causes marked potentiation of the effects of hyperthermia (45 degrees C) on HA-1 Chinese hamster ovary cells. The effects of the polycation appear to be mediated at the cell surface and are largely reversed by removal of DEAE-dextran with the polyanion dextran sulphate. Maximal potentiation is observed when polycation and heat are given simultaneously. The polycation also inhibits the capping of concanavalin-A acceptors when used singly and is additive with heat in inhibiting capping; reduction in con-A capping may indicate decreased mobility of cell surface glycoproteins. The mechanism of heat potentiation by DEAE-dextran is not fully understood. Effects on surface charge and cytoskeleton-membrane interactions may be involved. However, the polycation appears to have promise, both in probing mechanisms of heat killing and as an adjuvant to heat treatment; potentiation occurs at extremely low DEAE-dextran levels, with considerable potentiation at a concentration of 0.4 microM.
mesh_terms: D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D006224:Cricetinae; D003412:Cricetulus; D003637:DEAE-Dextran / Q000494:pharmacology*; D016264:Dextran Sulfate; D003911:Dextrans / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D006358:Hot Temperature; D013997:Time Factors
chemical_list: D003911:Dextrans; D003637:DEAE-Dextran; D016264:Dextran Sulfate