Evaluation of Serum Adenosine Deaminase Levels in Wistar Rats Undergoing Neuropathic Pain and Treated with tDCS

Ricardo N. Goulart 1 , Priscila C. Crespo 1, Mayara S. Soares 1, Giovana D. Gamaro 1, Francieli M. Stefanello 1, Ronaldo F. P. Castanho 1, Sara F. Nunes 1, Izabel C. de Souza 1

1. Cell Modulatory Laboratory – Institute of Biology - Department of Morphology - Federal University of Pelotas - Pelotas, Rio Grande do Sul, Brazil.

OBJECTIVE: To evaluate the relation between adenosine deaminase (ADA) activity and transcranial direct current stimulation (tDCS) in rats with induced neuropathic pain.

METHODS: 45 male Wistar rats, aged 60 days, were randomized into 9 groups: control-total, control-sham, control-tDCS, sham injury-control tDCS, sham injury-sham tDCS, sham injury-tDCS, injured-control tDCS, injured-sham tDCS and injured- tDCS, with approval by the local Animal Experimentation Ethics Committee (10480-14). In the injury group, there was a constriction of the right sciatic nerve. In the sham group, the same procedure, but without constriction and with nerve exposure. Fourteen days after the procedures, the animals in the injury groups were treated with continuous electrical stimulation of 0.5?A, for 20 minutes, over 8 consecutive days and those animals of the sham group submitted to the same process, without connecting the electrodes to the battery. Therefore, 8 days after the last tDCS session occurred the euthanasia, blood collection and centrifugation for the obtainment of serum. Subsequently, was the measurement of ADA activity and statistical analysis by one-way ANOVA, followed by Student-Newman-Keuls.

RESULTS: The data demonstrate the effectiveness of the treatment, in the long term, with the increase of the pain threshold in the rats submitted to the chronic pain model, p<0.05. However, tDCS was not able to modify ADA activity in the control and sham groups.

CONCLUSIONS: The ADA activity was not modified by the treatment. However, further studies are needed to elucidate the relation between the enzyme and tDCS in animal models of chronic pain.

KEYWORDS: ADA, TDCS, Neuropathic Pain

ACKNOWLEDGMENTS: Federal University of Pelotas (UFPel), Cell Modulatory Laboratory (NeuroCell) and Bioengineering of the Clinic Hospitals of Porto Alegre (HCPA).

FUNDING/FINANCIAL SUPPORT: CAPES (Coordination for the Improvement of Higher Education Personnel) and CNPq (National Council for Scientific and Technological Development)

DOI: https://doi.org/10.21801/ppcrj.2020.S1.26