RESUMO
Lidocaine blocks nociceptive fibers, preventing initial wound signaling and mast cell degranulation. It is hypothesized that epinephrine and buffer affect the wound healing by potentiating lidocaine blockage. This double-blind, randomized, self-controlled study investigated this possibility using male Wistar rats, which were injected with 2 mL of different solutions into the left and right sides of the back. Then, each side was incised and sutured. Sixty rats were divided in three groups: saline solution (SS) and lidocaine; lidocaine and lidocaine with buffer; lidocaine with epinephrine and lidocaine with epinephrine and buffer. Half of each group was sacrificed 7 days after surgery and the remaining after 21 days. A sample of each wound was obtained and quantified for the level of collagen present using computer morphometry and for mast cell quantity. There were no differences between animals with regard to the collagen. However, mast cell levels in the same animal significantly differed between SS × lidocaine. Comparison of the same injected substance between animals with different healing dates showed a significant effect on collagen SS and on all mast cells, except SS. Lidocaine affected collagenization and decreased the initial quantity of mast cells at the wound site.
Assuntos
Epinefrina/farmacologia , Lidocaína/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Soluções Tampão , Contagem de Células , Colágeno/metabolismo , Epinefrina/administração & dosagem , Lidocaína/administração & dosagem , Masculino , Mastócitos/patologia , Ratos , Ratos Wistar , Pele/lesões , Pele/metabolismo , Pele/patologiaRESUMO
BACKGROUND AND OBJECTIVE: The treatment of calcaneal tendon injuries requires long-term rehabilitation. Ultrasound (US) and low-level laser therapy (LLLT) are the most used and studied physical agents in the treatment of tendon injuries; however, only a few studies examined the effects of the combination of US and LLLT. Therefore, the purpose of this study was to investigate which treatment (the exclusive or combined use of US and LLLT) most effectively contribute to tendon healing. STUDY DESIGN/MATERIALS AND METHODS: This was a controlled laboratory study with 50 rats whose Achilles tendon was injured by direct trauma. The rats were randomly divided into five groups and treated for 5 consecutive days, as follows: group 1 (control) received no treatment; group 2 was treated with US alone; group 3 was treated with LLLT alone; group 4 was treated first with US followed by LLLT; and group 5 was treated first with LLLT followed by US. On the sixth post-injury day, the tendons were removed and examined by polarized light microscopy. The organization of collagen fibers was assessed by birefringence measurements. Picrosirius-stained sections were examined for the presence of types I and III collagen. RESULTS: There was a significantly higher organization of collagen fibers in group 2 (US) than in the control group (P = 0.03). The amount of type I collagen found in groups 2 (US), 3 (LLLT), and 5 (LLLT + US) was significantly higher than that in the control group (P Assuntos
Tendão do Calcâneo/lesões
, Colágeno/ultraestrutura
, Terapia com Luz de Baixa Intensidade
, Traumatismos dos Tendões/terapia
, Terapia por Ultrassom
, Tendão do Calcâneo/efeitos da radiação
, Tendão do Calcâneo/ultraestrutura
, Animais
, Colágeno/efeitos da radiação
, Masculino
, Microscopia
, Distribuição Aleatória
, Ratos
, Ratos Wistar
, Ruptura/patologia
, Cicatrização/efeitos da radiação