EFEK PEMBERIAN KALSITRIOL (1α,25 (OH)2 D3) TERHADAP KADAR CYCLIC AMP KULTUR KARDIOMIOSIT

Cut Sidrah Nadira

Abstract


Defisiensi kalsitriol dapat meningkatkan faktor risiko terjadinya penyakit kardiovaskular. Hal ini dikaitkan dengan penurunan fosforilasi troponin I (TnI) di Ser23/24. Fosforilasi TnI di Ser23/24 berperan dalam regulasi Mg-ATPase miofilamen dan sensitivitas miofilamen terhadap Ca2+ yang selanjutnya mempengaruhi respon frekuensi dan kekuatan ejeksi ventrikel. Ser23/24 TnI ini diketahui merupakan substrat spesifik PKA. Penelitian ini bertujuan untuk mempelajari apakah efek kalsitriol terhadap peningkatan fosforilasi TnI mempunyai jalur mekanisme aksi yang juga melalui cAMP/PKA. Penelitian ini merupakan eksperimental murni menggunakan rancangan pre-post test with control group dengan sampel kultur primer kardiomiosit Sprague-Dawley jantan dewasa. Kardiomiosit diinkubasi kalsitriol selama 5 menit kemudian kadar cAMP diukur menggunakan metode ELISA. Hasil penelitian tidak menunjukkan adanya korelasi antara peningkatan TnI terfosforilasi dengan kadar cAMP (p>0,05). Penelitian ini masih belum dapat membuktikan adanya jalur aktivasi cAMP/PKA oleh kalsitriol dalam mekanisme peningkatan TnI terfosforilasi pada kardiomiosit.


Keywords


kalsitriol, kontraktilitas, kardiomiosit, troponin I

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References


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DOI: https://doi.org/10.29103/averrous.v1i2.397

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