title: Interaction between 3,5-diacetyl-1,4-dihydropyridines and ampicillin, and erythromycin on different E. coli strains.
abstract: Eleven analogues of nifedipine (NP) showed synergistic interactions with ampicillin (Ap) and erythromycin (Er) on Escherichia coli K12LE140/F'lac. The antibacterial effect of Ap was enhanced by most analogues but compound (G9) and (+/-)-verapamil (VP) were antagonistic. Two of the 11 compounds (G7, G8) were synergistic with Er and four were additive. With a sensitive clinical isolate of E. coli Gy-1/Ap(sens)Er(res), compound G1 antagonized the antibacterial effect of Ap and a synergistic effect was found in the combination of Er with G4, G5, G6 or G7. None of the drugs had any effect on a multidrug resistant (MDR) clinical isolate of E. coli Gy-2/Ap(res)Er(res).
authors.affiliation: Department of Microbiology, Albert Szent-Györgyi Medical University, Szeged, Hungary.
authors.forename: Györgyi
authors.initials: G
authors.lastname: Gunics
authors.forename: Sándor
authors.initials: S
authors.lastname: Farkas
authors.forename: Noboru
authors.initials: N
authors.lastname: Motohashi
authors.forename: Anamik
authors.initials: A
authors.lastname: Shah
authors.forename: Gaveriya
authors.initials: G
authors.lastname: Harsukh
authors.forename: Masami
authors.initials: M
authors.lastname: Kawase
authors.forename: Joseph
authors.initials: J
authors.lastname: Molnár
mesh_terms: D000667:Ampicillin / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D004095:Dihydropyridines / Q000737:chemistry / Q000494:pharmacology*; D004347:Drug Interactions; D024881:Drug Resistance, Bacterial; D004917:Erythromycin / Q000494:pharmacology*; D004926:Escherichia coli / Q000145:classification* / Q000187:drug effects* / Q000235:genetics; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D009543:Nifedipine / Q000031:analogs & derivatives* / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D004095:Dihydropyridines; D004917:Erythromycin; D000667:Ampicillin; D009543:Nifedipine