A dielectric relaxation study on the effects of the antitumor drugs Lonidamine and Rhein on the membrane electrical properties of Ehrlich ascites tumor cells.
The effects of the anti-tumor drugs lonidamine and rhein on the plasma membrane electrical properties of Ehrlich ascites tumor cells were investigated and compared. Dielectric relaxation measurements in the radiowave frequency range (10(4) to 10(8) Hz) as well as at higher frequencies (10(4) to 10(9) Hz) were performed and the data elaborated using a "single-shell" fitting procedure. The results obtained in both frequency ranges indicate that membrane conductivity and membrane permittivity are altered by 200 microM Lonidamine while 150 microM rhein induces only very slight variations in these two plasma membrane parameters. The usefulness of the dielectric relaxation technique described here in evaluating antitumor drugs and improving clinical protocols is discussed.
Santini
M T
MT
Laboratorio di Ultrastrutture, Istituto Superiore di Sanità, Roma, Italy.
Cametti
C
C
Zimatore
G
G
Malorni
W
W
Benassi
M
M
Gentile
F P
FP
Floridi
A
A
Indovina
P L
PL
D000818:Animals; D000880:Anthraquinones / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D002286:Carcinoma, Ehrlich Tumor / Q000503:physiopathology*; D002462:Cell Membrane / Q000187:drug effects / Q000502:physiology*; D004553:Electric Conductivity; D007191:Indazoles / Q000494:pharmacology*; D051379:Mice; D009247:NADH, NADPH Oxidoreductases / Q000037:antagonists & inhibitors; D011846:Radio Waves; D014407:Tumor Cells, Cultured
D000880:Anthraquinones; D000970:Antineoplastic Agents; D007191:Indazoles; D009247:NADH, NADPH Oxidoreductases; C016371:lonidamine; C020491:rhein