Vildan TOĞRUL, Nesrin GÜNAYDIN, Burak TANYILDIZ

ŞAŞILIKTA EKSTRAOKÜLER KASLARDA KALSİYUM ADENOZiN 5’ TRiFOSFATAZ AKTİVİTESİ

AMAÇ: Bu çalışma extraoküler kaslardaki kalsiyum adenozin 5’-trifosfataz Ca2+-ATPaz enzim aktivite düzeyinin şaşılık ve kontrol gruplarında değerlendirilmesi ve karşılaştırılması amaçlamıştır.GEREÇ VE YÖNTEM: Şaşılık grubu (grup 1), horizontal kaslarına rezeksiyon yapılan 19 hastanın 20 gözünden oluşmuştur. Daha önce organ nakli için gözünü bağışlamış, ölüm nedeni belli, herhangi bir sistemik ya da göz hastalığı olmayan 5 göz ise kontrol grubu (grup 2) olarak alınmıştır. Her iki gruba aynı miktarda rezeksiyon uygulanmıştır. Enzim aktivitesi, Ca2+-ATPaz aktivitesi sırasında açığa çıkan inorganic fosfat (Pi) düzeyi ile ölçülmüştür.BULGULAR: 'Grup 1’de ortalama aktivite 100.07 ± 12.75 Pimg-1 0.90 min-1 olarak ölçülürken, Grup 2’de 165.94 ± 13.60 nmolPi mg-1 0.90 min-1 olarak ölçülmüştür. Grup 1’ de enzim aktivitesi, grup 2’ye gore istatistiksel olarak anlamlı düzeyde daha düşük bulunmuştur (p < 0.01).SONUÇ: Şaşılık cerrahisi sırasında rezeke edilen kaslarda düşük Ca2+-ATPaz enzim aktivitesinin bulunması şaşılık patofiyolojisindeki olası rolünün bir göstergesi olabilir.

Anahtar Kelimeler:

Şaşılık, Extraoküler kas, Ca2+-ATPase

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

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.

Keywords:

Strabismus , Extraocular muscle, Ca2+-ATPase,

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