Abstract ID: 3765

Primary Topic: Whole systems and acupuncture (including TCM and Ayurveda)
Secondary Topic: Integrative medicine delivery models

Electroacupuncture induced analgesia in an animal model of complex regional pain syndrome type 1 (CRPS-I): evaluation of peripheral endothelinergic receptors
Daiana C. Salm, Master degree; Leidiane Mazzardo-Martins, PhD, University of Federal of Santa Catarina, Florianópolis, Brazil; Francisco Cidral-Filho, PhD, University of Southern Santa Catarina, Palhoça, Brazil; Júlia Koerich, Graduate; Kamilla Pamplona, Graduate; Luiz Augusto Belmonte, Doctorate degree, University South of Santa Catarina, Palhoça, Brazil; Ari Moré, PhD, Universitary hospital, Florianópolis, Brazil; Verônica V. Horewicz, PhD; Anna Paula Piovezan, PhD; Daniela D. Lüdtke, Doctorate degree, University South of Santa Catarina, Palhoça, Brazil; Elisa C. Winkelmann Duarte, PhD, University of Federal of Santa Catarina, Florianópolis, Brazil; Afonso Salgado, PhD; Daniel F Martins, PhD, University of Southern Santa Catarina, Palhoça, Brazil

Late Breaker: No

Purpose

To evaluate the possible antihyperalgesic effect of electroacupuncture (EA) in a model of CRPS-I as well as the involvement of endothelinic ETB receptors in this effect.

Methods/Session Format

Ischemia-Reperfusion (I/R) was induced in anesthetized mice over a period of 3 hours (chloral hydrate 7%, 0.6 ml / kg, ip + 20% supplements at the end of the first and second hour) with a 1.2 mm internal diameter O-ring elastic band placed around the right ankle joint. Mechanical hyperalgesia was assessed as response frequency to 10 presentations of a 0.4g von Frey filament. For EA the animals were anesthetized (2% isoflurane) while acupoints ST-36 and SP-6 were punctured (0.18 mm x 8 mm acupuncture needles) and stimulated with an electroacupuncture device (NKL-608 - frequencies 2 Hz and 10 Hz with alternating polarity and intensity of 2 to 3 mAc for 20 minutes. The involvement of endothelinergic type B receptors (ETB) were evaluated on the 14th day after paw I/R in Experiment #1: to check if the selective ETB receptor agonist Sarafotoxin (i.pl., 10 μl) would decrease mechanical nociception induced by I/C and whether this effect would be prevented by 15 min prior administration of the ETB receptor antagonist Bq-788 (i.pl., 10 μl). Experiment 2: to evaluated whether pre-treatment with Bq-788 (i.pl., 10 μl, 15 minutes prior) would prevent the anti-hyperalgesic effect of EA. Experiment # 3: to evaluated the possible additive the effect of EA and Sarafotoxin (i.pl., 10 μl) (15 min interval between treatments).

Results

I/R induced marked and long-lasting mechanical hyperalgesia. EA reduced mechanical hyperalgesia on all treatment days (days 3 to 21 post I/R), with effects lasting for up to 1 hour post treatment (P<0.05 - 0.001). Sarafotoxin (i.pl., 10 μl) decrease mechanical nociception induced by I/C with effect prevented by 15 min prior administration with Bq-788 (i.pl., 10 μl). Pre-treatment with Bq-788 (i.pl., 10 μl, 15 minutes prior) prevented the anti-hyperalgesic effect of EA. EA and Sarafotoxin (i.pl., 10 μl) treatment combination induced 2h analgesia, which is twice longer than each separate treatment (1 hour analgesia).

Conclusions

Electroacupuncture induced analgesia is dependent upon peripheral endothelinergic receptors activation in an animal model of complex regional pain syndrome type 1 (CRPS-I).