Peningkatan Konduktansi Maksimal Ion Kalium Setelah Pemberian 7-Ketokolesterol pada sel PC-12 SecaraIn vitro

Indra Kusuma

Abstract


Stroke menyebabkan kondisi hipoksia-iskemia yang menimbulkan berbagaikerusakan. Perubahan neurokimia otak pada stroke menyebabkan oksidasikolesterol. Produk oksidasi kolesterol yaitu 7-ketokolesterol diketahui mengubahkomposisi lipid raft, sifat protein membran dan meningkatkan eksositosisneurotransmitter. Kanal Kv berperan pada terminasi eksositosis danmempertahankan keseimbangan ionik sel saraf. Pemberian 7-ketolesterol padasel PC-12 bertujuanmelihat respon kanal Kv. Perekaman patch clamp dilakukandengan tehnik whole-cell secara voltage clamp. Hasil eksperimen terekamkenaikan arus listrik (p<0.05) pada potensial membran negatif, penurunanreversal potensial (p>0.05) dan peningkatan konduktansi maksimal ion kalium(p<0.05). Hasil eksperimen berupa perubahan konduktansi maksimalmenunjukkan pengaruh 7-ketokolesterol pada kinetika dan fungsi kanal Kv yangdiperkirakan sebagai akibat perubahan interaksi lipid-protein pada lipid raft.Pada konteks stroke respon kanal Kv turut berkontribusi pada prosesneurotoksisitas yang berujung pada kematian sel.Stroke menyebabkan kondisi hipoksia-iskemia yang menimbulkan berbagaikerusakan. Perubahan neurokimia otak pada stroke menyebabkan oksidasikolesterol. Produk oksidasi kolesterol yaitu 7-ketokolesterol diketahui mengubahkomposisi lipid raft, sifat protein membran dan meningkatkan eksositosisneurotransmitter. Kanal Kv berperan pada terminasi eksositosis danmempertahankan keseimbangan ionik sel saraf. Pemberian 7-ketolesterol padasel PC-12 bertujuanmelihat respon kanal Kv. Perekaman patch clamp dilakukandengan tehnik whole-cell secara voltage clamp. Hasil eksperimen terekamkenaikan arus listrik (p<0.05) pada potensial membran negatif, penurunanreversal potensial (p>0.05) dan peningkatan konduktansi maksimal ion kalium(p<0.05). Hasil eksperimen berupa perubahan konduktansi maksimalmenunjukkan pengaruh 7-ketokolesterol pada kinetika dan fungsi kanal Kv yangdiperkirakan sebagai akibat perubahan interaksi lipid-protein pada lipid raft.Pada konteks stroke respon kanal Kv turut berkontribusi pada prosesneurotoksisitas yang berujung pada kematian sel.

Keywords


7-ketokolesterol; Kanal Kv; Lipid raft; Patch clamp

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DOI: https://doi.org/10.33476/jky.v20i2.159

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