Study of the dose-dependence of the laser of low power, in the regeneration of sciatic nerve of rats after injury for crushing

• Grant number: 11/09069-8
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: July 01, 2011
• End date: January 31, 2013
• Field of knowledge: Health Sciences - Physiotherapy and Occupational Therapy
• Principal Investigator: Claudio Henrique Barbieri
• Grantee: Rodrigo Antonio Carvalho Andraus
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

We will verify if the irradiation with low power laser accelerates the morphological and functional recovery of peripheral nerves, in proportion to dose applied, after a crush injury. For this, 72 Wistar rats (weighing approximately 220 g), will be submitted to a crushing injury to the sciatic nerve with a special gripper calibrated with a pre-determined load of 5.000 grams, applied for 10 minutes. The crushed nerves will be submitted to irradiation of laser diode (AsGaAL) low power (100 mW of power, 830 nm wavelengths, and continuous mode). The animals will be divided into six groups; a control group, a injured group without treatment and 4 injured and treated groups, with different doses of laser (35, 70, 140 and 280 J/cm2). The Functional Index Sciatic will be evaluated, starting before surgery and every week after the injury and treatment with the laser. On the 21st postoperative day, the animals will be sacrificed with excessive dose of anesthetic and the muscles, nerves and ganglia will be dissected and analyzed by biomechanical testing and molecular analysis of protein expression (zimografia, immunofluorescence and western blot). Gastrocnemius muscle will be submitted to a mechanical testing of traction, where maximal load and stiffness will be measured. In the protein expressions analysis the tibial anterior muscle will be analyzed by zimografia, and the sciatic nerve and the ganglia of the dorsal root will be analyzed by immunofluorescence and western blot. All data will be submitted to the regression analysis linear, with level of significance set at 5% (p <0,05). (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)

CARVALHO ANDRAUS, RODRIGO ANTONIO; MAIA, LUCIANA PRADO; DE SOUZA LINO, ANDERSON DIOGO; PARRON FERNANDES, KAREN BARRON; DE MATOS GOMES, MARCOS VINICIUS; DE JESUS GUIRRO, RINALDO ROBERTO; BARBIERI, CLAUDIO HENRIQUE. LLLT actives MMP-2 and increases muscle mechanical resistance after nerve sciatic rat regeneration. Lasers in Medical Science, v. 32, n. 4, p. 771-778, MAY 2017. (11/09069-8)