CALCIUM ADENOSINE 5’ TRIPHOSPHATASE ENZYME ACTIVITY IN EXTRAOCULAR MUSCLES IN STRABISMUS

Abstract

OBJECTIVE: This study aims to assess and compare the level of the calcium adenosine 5’-triphosphatase (Ca2+-ATPase) enzyme activity in resected extraocular muscles of strabismus and control groups.MATERIAL AND METHODS: The level of Ca2+-ATPase enzyme activity was evaluated in the extraocular horizontal muscles resected from twenty eyes of 19 patients who underwent strabismus surgery (group 1) and extraocular horizontal muscles samples taken from five eyes of 5 corneal transplant donors (control group - group 2). Enzyme activity was measured via inorganic phosphate (Pi) levels released during Ca2+-ATPase activity.RESULTS: The average activity was calculated as 100.07±12.75 nmol Pi mg-1 0.90min-1 in group 1 and as 165.94±13.60 nmol Pi mg-1 0.90 min-1 in group 2. The enzyme activity in group 1 was significantly lower than in group 2 (p <0.01).CONCLUSIONS: The low level of Ca2+-ATPase enzyme activity in muscles that were resected during strabismus surgery might be an indicator for their possible role in pathophysiology of strabismus.