Giant fibres in fetal ovine muscle
2014 New Directions in Biology and Disease of Skeletal Muscle Conference, Chicago, United States Of America, 29 June - 02 July 2014, pp.26, (Full Text)
- Publication Type: Conference Paper / Full Text
- City: Chicago
- Country: United States Of America
- Page Numbers: pp.26
- Istanbul University Affiliated: Yes
Abstract
The study examined the occurance of giant fibres in fetal muscle from undernourished and control ewes. Giant fibres were rounded in shape and larger than adjacent normal fibres. They showed generally strong ATPase –alkaline positive reaction. Based on ATPase staining the giant fibres are classified as type II or fast fibres. In EM, Transverse sections showed that regular hexagonal array of myofilaments was absent in the giant fibres. Longitudinal sections showed that sarcomer length was shorter than normal fibres. Giant fibres are clearly hypercontracted fibres. Undernutrition did not seem to have significant effect on the occurance of giant fibre. In the two restricted animals the high incidence of giant fibres was observed. We suggest that giant fibres, since they are present prenatally, results from defects in the developing muscle fibres leading to structural and metabolic anomalies within the fibres. These defects such as inadequte amount of sarcoplasmic reticulum, leaky membranosus of sarcoplasmic reticulum or deficiency in the production of ATP by the mitochondria prevents relaxation of muscle and causes hypercontraction.