활성산소가 골아세포내 Ca^(2) 활성도에 미치는 영향 = Effects of reactive oxygen species on the intracellular Ca^(2) activity in the osteoblast-like cells

다국어 초록 (Multilingual Abstract)

Physiological activity of osteoblast is known to be closely related to the increase of intracellular Ca^(2+) activity (［Ca^(2+)］_(i)) in osteoblast. Reactive oxygen species such as H_(2)O_(2) plays an important role in regulation of cellular functions such as transcription, growth factor action and ion transport.
In this study, the effects of reactive oxygen species on the intracellular Ca^(2+) regulation in osteoblast-like cells (OLCs) were investigated by measuring Ca^(2+) activities with cell imaging techniques. OLCs were isolated from femur and tabia of neonatal rats, and cultured for 7 days. The cultured OLCs were loaded with a Ca^(2+)-sensitive fluorescent dye, Fura-2, and fluorescence images were monitored with a cooled CCD camera and analyzed with an image analyzing software. The results are as follows:
(1) ［Ca^(2+)］_(i) of OLC increased as the H_(2)O_(2) concentration in superfusing Tyrode solution was raised, in two fashions. The OLCs with lower basal Ca^(2=) activities yielded a transient Ca^(2+) increase, the Ca^(2+) spike, while OLCs with higher basal Ca^(2+) activities showed continuous increase in ［Ca^(2+)］_(i) leading to the cell death. (2) tBHP did not have a significant effect on Ca^(2+)-dependence of ［Ca^(2+)］_(i). (3) Ca^(2+) spikes, generated when Na^(+) in the supefusing solutions was removed, were blocked by tBHP and H_(2)O_(2). However, H_(2)O_(2) induced a continuous Ca^(2+) release from the internal Ca^(2+) stores under the extracellular Na^(+) and Ca^(2+)-free condition. (4) Ca^(2+) efflux generated by Na^(+)-Ca^(2+) exchange was not affected by H_(2)O_(2).
These results suggest that H_(2)O_(2) modulates the intracellular Ca^(2+) activity in osteoblast by the modifications of the Ca^(2+) transport across the cell membrane and Ca^(2+) release from the internal stores. Further studies with histochemical and biochemical techniques will enrich the findings of the study.

목차 (Table of Contents)

• 목차
• List of Figures = ⅰ
• List of Tables = ⅱ
• ABSTRACT = ⅲ
• Ⅰ. 서론 = 1
• Ⅱ. 실험재료 및 방법 = 6
• 1. 골아세포의 분리 및 배양 = 6
• 2. 형광감성제 주입 = 6
• 3. 세포내 Ca^(2+) 활성도 변화의 영상화 = 7
• 4. 실험 용액 = 8
• Ⅲ. 결과 = 13
• 1. 활성산소 농도 변화가 골아세포[Ca^(2+)]_(i)에 미치는 영향 = 13
• 2. 활성산소가 [Ca^(2+)]_(i)의 Ca^(2+) 의존성에 미치는 영향 = 13
• 3. 활성산소가 [Ca^(2+)]_(i)의 Na^(+) 의존성에 미치는 영향 = 18
• 4. 활성산소가 [Ca^(2+)]_(i)의 Ca^(2+) spike 형성에 미치는 영향 = 20
• 5. 활성산소가 세포막을 통한 Ca^(2+) 이동에 미치는 영향 = 20
• Ⅳ. 고찰 = 23
• Ⅴ. 결론 = 27
• 참고문헌 = 28