Collagen metabolism of XXXX skeletal muscle during the repair of exercise injuries.

@entity39 @entity19 @entity720 @entity10783 @entity121
The activities of @entity10783 4-hydroxylase and beta-glucuronidase, the concentration of @entity720 as well as reticulin and collagen type III, IV and V stainings were followed in skeletal muscle during a 20-day period after a 9-h treadmill running in untrained and trained male @entity19 , aged 4-6 months. The prolonged 9-h running of untrained @entity19 temporarily increased @entity10783 4-hydroxylase activity 2, 5 and 10 days after exercise, more prominently in the red than in the white part of quadriceps femoris-muscle, and in analogical manner as beta-glucuronidase activity in tibialis anterior-muscle. Twenty days after exercise these enzymatic activities were back to the control level. The @entity720 content of red muscle was increased for 10 and that of white muscle for 20 days after the exertion. Training for 45 days did not affect @entity720 content and @entity10783 4-hydroxylase activity was at the control level after the training. A 9-h exercise increased @entity10783 4-hydroxylase activity much less in trained muscle than in the untrained muscle and did not affect muscle collagen content. Histological observations showed fiber @entity39 2 days and signs of fiber regeneration 5 days after the exertion in untrained @entity19 . Twenty days afterwards the regeneration was nearly completed. Reticulin staining was increased in injured muscle areas 10-20 days after the exertion. In immunohistochemical staining, antibodies to all studied collagen types (type III, IV and V) showed increased staining 5-20 days after the exertion in the areas of @entity121 and regeneration.(ABSTRACT TRUNCATED AT 250 WORDS)
