Effect of microcurrent electrical tissue stimulation on equine tenocytes in culture.
OBJECTIVE
To determine effects of microcurrent electrical tissue stimulation (METS) on equine tenocytes cultured from the superficial digital flexor tendon (SDFT).


METHODS
SDFTs were collected from 20 horses at slaughter.


METHODS
Tenocytes were isolated following outgrowth from explants and grown in 48-well plates. Four methods of delivering current to the tenocytes with a METS device were tested. Once the optimal method was selected, current consisting of 0 (negative control), 0.05, 0.1, 0.5, 1.0, or 1.5 mA was applied to cells (8 wells/current intensity) once daily for 8 minutes. Cells were treated for 1, 2, or 3 days. Cell proliferation, DNA content, protein content, and apoptosis rate were determined.


RESULTS
Application of microcurrent of moderate intensity increased cell proliferation and DNA content, with greater increases with multiple versus single application. Application of microcurrent of moderate intensity once or twice increased protein content, but application 3 times decreased protein content. Application of current a single time did not significantly alter apoptosis rate; however, application twice or 3 times resulted in significant increases in apoptosis rate, and there were significant linear (second order) correlations between current intensity and apoptosis rate when current was applied twice or 3 times.


CONCLUSIONS
Results of the present study indicate that microcurrent affects the behavior of equine tenocytes in culture, but that effects may be negative or positive depending on current intensity and number of applications. Therefore, results are far from conclusive with respect to the suitability of using METS to promote tendon healing in horses.
Lin
Yi-Lo
YL
Department of Equine Sciences, Faculty of Veterinary Medicine, State University of Utrecht, Utrecht, The Netherlands.
Moolenaar
Hugo
H
van Weeren
P René
PR
van de Lest
Chris H A
CH
D000818:Animals; D017209:Apoptosis; D049109:Cell Proliferation; D002478:Cells, Cultured; D004558:Electric Stimulation; D006736:Horses; D013710:Tendons / Q000166:cytology*