Elif ÖZTETİK

A study of calcium release from rat liver microsomes by thapsigargicin induction

Özet: Bu çalışmanın ana amacı hücre içindeki Ca2+ depolarından Ca2+ salınımına tapsigargisinin etkisinin test edilmesi ve bunun tapsigargin etkisi ile karşılaştırılmasıdır. Çalışmada tümor promotörü tapsigargisinin hücre içindeki Ca2+’a etkileri tanımlanmıştır. Bu nedenle, sıçan endoplazmik retikulum subsellüler (hücrealtı) fraksiyonları (mikrozomlar) kullanılmış ve Ca2+ hareketleri spektrofluorimetre ile ölçülmüştür. Mikrozomlardaki Ca2+ salınımı Fluo-3 çalışmaları ile takip edilmiştir. Elde edilen bulgular değerlendirildiğinde, tapsigargisinin de tapsigargin gibi hücre içi Ca2+ depolarını boşalttığı, hücre içi serbest Ca2+ konsantrasyonunu ([Ca2+]i) arttırdığı ve ER Ca2+-ATPaz için güçlü ve özgül bir inhibitör olduğu kanısına varılmıştır.

Tapsigargisin indüksiyonu ile sıçan karaciğer mikrozomlarından kalsiyum salınımı üzerine bir çalışma

Summary: The primary aim of the study was to test the influences of thapsigargicin in releasing Ca2+ from the intracellular Ca2+ stores and comparing it with the effects of thapsigargin. In this study, the effect of tumour promoter thapsigargicin on intracellular Ca2+ has been described. Therefore, rat liver endoplasmic reticulum subcellular fractions (microsomes) were employed and Ca2+ movements measured by spectrofluorimeter. Fluo-3 studies were used to follow Ca2+ release in experiments with microsomes. When results are evaluated, it has been concluded that like thapsigargin, thapsigargicin has the ability of discharging the intracellular Ca2+ stores, increasing the intracellular free Ca2+ concentration ([Ca2+]i) and being a potent and specific inhibitor of the ER Ca2+-ATPase.

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