Evaluation of myotoxicity and neurotoxicity ( neuromuscular junction focus ) after bupivacaine application followed by laser therapy

• Grant number: 13/26649-3
• Support Opportunities: Regular Research Grants
• Start date: August 01, 2014
• End date: July 31, 2016
• Field of knowledge: Health Sciences - Medicine
• Principal Investigator: Selma Maria Michelin Matheus
• Grantee: Selma Maria Michelin Matheus
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil
• Associated researchers: Cristiane Neves Alessi Pissulin ; Maeli Dal Pai

Abstract

Local anesthetics are used for pre and postoperative pain and chronic pain. Their two main limitations are inflammation, myotoxicity and neurotoxicity. Bupivacaine is considered among local anesthetics, the most myotoxic. Moreover, laser therapy of low intensity (LLLT) has been prescribed as a complementary therapy that has anti - inflammatory action after tissue injury, it promotes muscle satellite cell proliferation, angiogenesis and expression of growth factors, acting on muscle regeneration. The aim of this project is to investigate the effects of LLLT after bupivacaine injection. 36 adult male Wistar rats will receive bupivacaine 0.5 % application on right antimere, and sodium chloride 0.9 % on left antimere (control). After 24 hours, the animals will be divided into two equal groups: only one group will receive one daily application of LLLT on both antimeres for 5 consecutive days. After this period, the animals will be euthanized, the superficial portion of sternomastoid muscle and the associated nerve will be removed and analyzed by the following methods: a) Levels of inflammation : by Western Blot of TNFalpha b) Myotoxicity: quantification of Creatine Kinase (CK) and Lactate Dehydrogenase (LDH), morphological and ultrastructural analysis of muscle fibers of sternomastoid muscle superficial portion c) Neurotoxicity : morphological, ultrastructural and morphometric analysis of the sternomastoid nerve as well as of the neuromuscular junctions associated ; Analysis of the acetylcholine receptors (nAChRs) distribution by confocal microscopy and Western Blot. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

ALESSI PISSULIN, CRISTIANE NEVES; HENRIQUE FERNANDES, ANA ANGELICA; SANCHEZ ORELLANA, ALEJANDRO MANUEL; ROSSI E SILVA, RENATA CALCIOLARI; MICHELIN MATHEUS, SELMA MARIA. Low-level laser therapy (LLLT) accelerates the sternomastoid muscle regeneration process after myonecrosis due to bupivacaine. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY, v. 168, p. 30-39, MAR 2017. (13/26649-3)

ALESSI PISSULIN, CRISTIANE NEVES; TOME DE SOUZA CASTRO, PAULA AIELLO; CODINA, FLAVIO; PINTO, CARINA GUIDI; VECHETTI-JUNIOR, IVAN JOSE; MICHELIN MATHEUS, SELMA MARIA. GaAs laser therapy reestablishes the morphology of the NMJ and nAChRs after injury due to bupivacaine. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY, v. 167, p. 256-263, FEB 2017. (13/26649-3)