Why don’t eye muscles get paralysed?February 12th, 2009 - 12:28 pm ICT by IANS
Sydney, Feb 12 (IANS) Researchers have found out why eye muscles remain unaffected by paralysis. The finding potentially opens the way to improved treatments of paralysed patients, and will also help investigations into cardiovascular diseases.
Nigel Laing and his team at the Western Australian Institute for Medical Research (WAIMR) have discovered the reason why patients suffering from muscle diseases caused by mutations in the skeletal muscle actin gene (responsible for muscle contraction) are able to maintain normal eye movements, despite paralysis.
Laing said the specific line of research was sparked when one of the team’s researchers Kristen Nowak attended a patient convention and noticed that even patients who were otherwise severely paralysed retained normal eye movement.
“We looked into this phenomenon and found that it had already been documented that eye muscles were not affected in patients with actin-based muscle diseases but, as there was no explanation as to why this occurred, we decided to conduct our own investigations,” he said.
“We found that eye muscles have a similar actin composition to that of the heart - which have high levels of cardiac actin and some skeletal muscle actin - different from skeletal muscles which are mainly composed of skeletal muscle actin,” he said.
“The high levels of cardiac actin in eye muscles explain why they’re not affected in skeletal muscle actin disease and tells us that if we’re able to increase the level of cardiac actin in muscles that are affected in these diseases, we may be able to treat these patients.”
During the research process led by WAIMR’s Gina Ravenscroft, a new technique to distinguish between the different muscle actins was developed in collaboration with the WAIMR-based Proteomics International, according to a WAIMR release.
The study was published in Neuromuscular Disorders.