Effects of small pulsed nanocurrents on cell viability in vitro and in vivo: implications for biomedical electrodes.
Using a custom-built, implantable pulse generator, we studied the effects of small pulsed currents on the viability on rat aortic-derived cells (RAOC) in vitro. The pulsed currents (0.37A/m(2)) underwent apoptosis within 24h as shown by the positive staining for cleaved caspase-3 and classically apoptotic morphology. Based on these findings, we examined the effects of nanocurrents in vivo. The pulse generator was implanted subcutaneously in the rat model. The electrode|tissue interface histology revealed no difference between the active platinum surface and the neighboring control surface, however we found a large difference between electrodes that were functional during the entire experiment and non-active electrodes. These non-active electrodes showed an increase in impedance at higher frequencies 21 days post-implantation, whereas working electrodes retained their impedance value for the entire experiment. These results indicate that applied currents can reduce the impedance of implanted electrodes.
Gabi
Michael
M
Laboratory of Biosensors and Bioelectronics, ETH Zurich, Zurich, Switzerland.
Bullen
Michael E
ME
Agarkova
Irina
I
Schmidt
Dörthe
D
Schoenauer
Roman
R
Brokopp
Chad
C
Emmert
Maximilian Y
MY
Larmagnac
Alexandre
A
Sannomiya
Takumi
T
Weber
Benedikt
B
Wilhelm
Markus J
MJ
Vörös
Janos
J
Hoerstrup
Simon P
SP
D000818:Animals; D020811:Biomedical Technology / Q000295:instrumentation*; D016923:Cell Death; D002470:Cell Survival; D017097:Electric Impedance; D004560:Electricity; D004566:Electrodes; D049329:Nanostructures / Q000737:chemistry*; D019919:Prosthesis Implantation; D051381:Rats; D017207:Rats, Sprague-Dawley