title: The influence of pluronics and their conjugates with proteins on the rate of oxygen consumption by liver mitochondria and thymus lymphocytes.
abstract: The membranotropic properties of block co-polymers and their protein conjugates were studied by their effect on the rate of oxygen consumption by isolated liver mitochondria and on thymus-derived lymphocytes. The block co-polymers consisted of poly(ethylene oxide) (PoE) [poly(ethylene glycol)] and poly(propylene oxide) (PoP) to give either PoE-PoP or PoE-PoP-PoE. Both types inhibited uncoupled respiration of liver mitochondria in a medium containing glutamate and malate and also of lymphocytes. They also uncoupled respiration in the presence of succinate in K(+)-containing medium and of lymphocytes. A method is described for linking protein to the block polymers to form conjugates. Such conjugates were formed from alpha-chymotrypsin, BSA and cytochrome c, all of which produced similar effects on the respiration of the isolated mitochondria and lymphocytes. The data suggest that both the block co-polymers and their protein conjugates inhibit the NADH dehydrogenase complex and induce a K(+)-conductivity of the mitochondrial inner membrane; the surface activity of the conjugates allows them to pass through the plasma membrane and interact with the mitochondrial inner membrane.
authors.affiliation: A. N. Belozersky Institute of Physcio-Chemical Biology, Moscow State University, Russia.
authors.forename: G P
authors.initials: GP
authors.lastname: Kirillova
authors.forename: E N
authors.initials: EN
authors.lastname: Mokhova
authors.forename: V I
authors.initials: VI
authors.lastname: Dedukhova
authors.forename: A N
authors.initials: AN
authors.lastname: Tarakanova
authors.forename: V P
authors.initials: VP
authors.lastname: Ivanova
authors.forename: N V
authors.initials: NV
authors.lastname: Efremova
authors.forename: I N
authors.initials: IN
authors.lastname: Topchieva
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D004852:Epoxy Compounds / Q000494:pharmacology*; D005260:Female; D066298:In Vitro Techniques; D008214:Lymphocytes / Q000187:drug effects* / Q000378:metabolism; D008930:Mitochondria, Liver / Q000187:drug effects* / Q000378:metabolism; D009245:NADH Dehydrogenase / Q000037:antagonists & inhibitors; D010101:Oxygen Consumption / Q000187:drug effects* / Q000502:physiology; D011092:Polyethylene Glycols / Q000494:pharmacology*; D011108:Polymers; D011485:Protein Binding; D051381:Rats; D013950:Thymus Gland / Q000166:cytology / Q000378:metabolism
chemical_list: D004852:Epoxy Compounds; D011108:Polymers; D011092:Polyethylene Glycols; D009245:NADH Dehydrogenase; C009068:propylene oxide