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Brazilian Journal of Oral Sciences

versão On-line ISSN 1677-3225

Braz. J. Oral Sci. vol.9 no.4 Piracicaba Out./Dez. 2010

 

ORIGINAL ARTICLE

 

Pain behavior to electroacupuncture in rabbit tooth pulp

 

 

Delane Viana GondimI; Krishnamurti de Morais CarvalhoII; Mariana Lima ValeIII

IMSc, Department of Clinical Medicine, Medical School, Federal University of Ceará, Fortaleza, CE, Brazil
IIDDS, Department of Physiology, State University of Ceará, Fortaleza, CE, Brazil
IIIDDS, Department of Physiology and Pharmacology, Medical School, Federal University of Ceará, Fortaleza, CE, Brazil

Correspondence to

 

 


ABSTRACT

AIM: The aim of this study was to verify the pain behavior to electroacupuncture (EACP) in rabbit tooth-pulp assay.
METHODS: Albino rabbits weighing 1.5-2.0 kg) were pretreated with saline or morphine (5mg/kg, e.v.) 10 min before the nociceptive test (NT). In another group, EACP (rectangular pulses, f1=2 Hz, f2=0.1 s, 3 mA) was applied in acupoints and sham points, before and during the NT. After 120 min, EACP was withdrawn and the nociceptive threshold was measured every 10 min until the initial nociceptive threshold was achieved.
RESULTS: EACP, using the Yintang, ST4 and ST5 acupoints, induced an increased in the nociceptive threshold and this effect persisted for up to 2 h, even after the removal of electric stimulation. Application of EACP at sham points did not show significant analgesic activity. The present results demonstrated that males presented a higher initial level of analgesia, but a poorer maintenance of analgesic effect after the EACP procedure, while females demonstrated a long lasting analgesic effect even after discontinuation of EACP.
CONCLUSIONS: EACP presented an analgesic effect in a rabbit tooth pulp assay that was probably due to the release of endogenous opioids. The duration of this analgesic effect seems to be different for males and females.

Keywords: electroacupuncture, tooth pulp, analgesic effect, endogenous opioids, pain.


 

 

Full text available only in PDF format.

 

 

Acknowledgments

The authors gratefully acknowledge the technical assistance of Rosa Germana da Silva Oliveira and Rosemayre Freire for the English revision. This work was supported by grants from Fundação Cearense de Apoio ao Desenvolvimento Científico e Tecnológico (FUNCAP). We also thank Dr. Roberto Brasil for his assistance during experimental model development.

 

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Correspondence to:
Delane Viana Gondim
Departamento de Medicina Clínica,
Faculdade de Medicina,
Universidade Federal do Ceará - UFC.
R. Cel. Nunes de Melo, 1127, Rodolfo Teófilo
60430-270 - Fortaleza, CE, Brasil.
Phone: +55-85-3366-8588
Fax: +55-85-3366-8333
E-mail: delanegondim@yahoo.com.br

Received for publication: January 10, 2010
Accepted: November 12, 2010