[The effects of anterior cruciate ligament resection and subsequent running training on muscles around the knee joint in rat].
The purpose of this study was to evaluate the effects of running training on the muscles in rat after resection of the anterior cruciate ligament (ACL). The biochemical and histochemical changes were analyzed in the muscles around the knee joint from which the ACL was dissected, and the rats were subsequently forced to undergo endurance running. After ACL resection, the wet weights of all muscles around the knee joint decreased but an increase was found in the number of slow-twitch fibers, especially in the vastus lateralis and vastus medialis muscles. The activities of glycolytic and oxidative enzymes in all muscles tended to decrease following resection. Rats which had undergone ACL resection were put through training in the form of appropriate endurance running, causing significant increases in the wet weights of all muscles, except for the vastus medialis, and a decrease in the number of slow-twitch fibers in the vastus medialis. In addition, all the enzyme activities tended to decrease following training. Therefore, the influences of ACL resection and subsequent running training were clearly demonstrated in the vastus medialis muscle. These changes may have been caused by joint instability and sensory reflex dysfunction by deafferentation from the ACL mechanoreceptor (joint-ligament receptor). To maintain knee muscle function, stability of the joint and restoration of the skeletomotor system from the ACL and the muscles around the knee joint is necessary.
Fujiya
H
H
Department of Orthopaedic Surgery, St. Marianna University School of Medicine, Kanagawa, Japan.
D000818:Animals; D000070598:Anterior Cruciate Ligament Injuries; D007719:Knee Joint; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008297:Male; D008465:Mechanoreceptors; D018482:Muscle, Skeletal / Q000201:enzymology / Q000473:pathology*; D009929:Organ Size; D010805:Physical Conditioning, Animal / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D012420:Running / Q000502:physiology*; D013385:Succinate Dehydrogenase / Q000378:metabolism
D007770:L-Lactate Dehydrogenase; D013385:Succinate Dehydrogenase