Comparison between technetium-99m-sestamibi and hydrogen-3-daunomycin myocardial cellular retention in vitro.
This study was undertaken to verify whether 99mTc-sestamibi uptake parallels that of 3H-daunomycin in cells treated with multidrug resistance (MDR) reversing agents. Since we have detected in a previous work a moderate typical MDR phenotype in rat cardiac cells, a model of cultured myocardial cells was used.


METHODS
Newborn-rat cultured myocardial cells were incubated 120 min with the MDR-reversing agent verapamil 50 microM, PSC833 1 microM or S9788 10 microM alone or in combination, and the cellular retention of 3H-daunomycin and 99mTc-sestamibi was counted.


RESULTS
Hydrogen-3-daunomycin cellular accumulation was never modified by more than 15% when compared to control values, while 99mTc-sestamibi decreased to 75% +/- 32% (m +/- s.d.) of controls in the presence of S9788 and to 44% +/- 19% when S9788 was associated with verapamil.


CONCLUSIONS
The variations of 99mTc-sestamibi and 3H-daunomycin cellular accumulation induced by MDR-reversing agents in cultured myocardial cells can be dramatically different. While some MDR-reversing agents can significantly increase the 3H-daunomycin retention in cardiac cells, they have unexpected effects on that of 99mTc-sestamibi.
Cayre
A
A
Department of Radiotherapy, Centre Jean Perrin, Clermont-Ferrand, France.
Moins
N
N
Finat-Duclos
F
F
Verrelle
P
P
Maublant
J
J
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism*; D000818:Animals; D000831:Animals, Newborn; D000970:Antineoplastic Agents / Q000493:pharmacokinetics* / Q000494:pharmacology; D002478:Cells, Cultured; D003524:Cyclosporins / Q000494:pharmacology; D003630:Daunorubicin / Q000493:pharmacokinetics*; D019008:Drug Resistance, Neoplasm; D019450:Genes, MDR / Q000187:drug effects; D006321:Heart / Q000000981:diagnostic imaging*; D066298:In Vitro Techniques; D009206:Myocardium / Q000166:cytology / Q000378:metabolism*; D010880:Piperidines / Q000494:pharmacology; D011877:Radionuclide Imaging; D051381:Rats; D017208:Rats, Wistar; D017256:Technetium Tc 99m Sestamibi / Q000493:pharmacokinetics*; D014227:Triazines / Q000494:pharmacology; D014316:Tritium / Q000493:pharmacokinetics; D014700:Verapamil / Q000494:pharmacology
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000970:Antineoplastic Agents; D003524:Cyclosporins; D010880:Piperidines; D014227:Triazines; D014316:Tritium; C077022:S 9788; D017256:Technetium Tc 99m Sestamibi; D014700:Verapamil; C070272:valspodar; D003630:Daunorubicin