title: Hyperbaric oxygen therapy treatment for the recovery of muscle injury induced in rats.
abstract: BACKGROUND
  We evaluated the effect of hyperbaric oxygen treatment (HBOT) in the recovery of muscle injury in rats.
  
  
  METHODS
  Twelve female Wistar rats, weighing 200-250 g, were submitted to contusion of the right gastrocnemius muscle. Animals were then randomly assigned to an untreated control group or an HBOT-treated group. The HBOT group was given three, 60-minute sessions of HBOT at 253 kPa pressure at 24, 48 and 72 hours post injury. After the last session all animals were sacrificed and both gastrocnemius muscles removed, the left muscle as an internal control. Blood samples were taken for creatine phosphokinase (CPK). Using a standard traction technique, the muscles were analysed for their biomechanical properties: hardness, maximum elongation and maximum weight.
  
  
  RESULTS
  Significant differences were found between uninjured and injured muscles and between untreated and HBOT groups in maximum weight and hardness: maximum weight in the non-treated group 18.27 ± 2.99 N versus 26.18 ± 2.84 N in the HBOT group (P = 0.007); hardness in the non-treated group 2.24 ± 0.38 103 N m⁻¹ versus 3.19 ± 0.32 10³ N m⁻¹ in the HBOT group (P = 0.001). The difference in maximum elongation was not significant (P = 0.793). CPK was significantly different between the two groups (non-treated 6,445 ± 387 i.u. L⁻¹; HBOT 4,551 ± 80 i.u. L⁻¹; P = 0.009).
  
  
  CONCLUSIONS
  HBOT seems to play a positive role in the recovery of induced muscle injury in rats. However relevant, these results cannot be extrapolated to humans, for whom further clinical studies are warranted.
authors: Faculty of Health Sciences, Fernando Pessoa University, Porto, Portugal.
authors: Mariana
authors: M
authors: Cervaens Costa Maia
authors: Hyperbaric Medicine Unit, Pedro Hispano Hospital, Matosinhos, Portugal.
authors: Oscar Ferraz
authors: OF
authors: Camacho
authors: Faculty of Pharmacy, University of Porto, Porto, Portugal.
authors: Agostinho Franklim
authors: AF
authors: Pinto Marques
authors: Faculty of Health Sciences, Fernando Pessoa University, Faculdade de Ciências da Saúde da Universidade Fernando Pessoa Rua Carlos da Maia 296, 4200 Porto Portugal, Phone: +35-(0)12-2507-1300, Fax: +35-(0)2250-7109, E-mail: pbarata@ufp.edu.pt.
authors: Pedro Miguel
authors: PM
authors: Barata de Silva Coelho
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena / Q000502:physiology; D003288:Contusions / Q000097:blood / Q000201:enzymology / Q000503:physiopathology / Q000628:therapy*; D003402:Creatine Kinase / Q000097:blood; D005260:Female; D006931:Hyperbaric Oxygenation / Q000379:methods*; D018482:Muscle, Skeletal / Q000293:injuries* / Q000473:pathology / Q000503:physiopathology; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar
chemical_list: D003402:Creatine Kinase
keywords: Hyperbaric oxygen; hyperbaric oxygen therapy; injuries; musculo-skeletal; research