Effect of radiation on the activity and expression of Ca(2+)-Mg(2+)-ATPase in rat masseter muscle / 中华口腔医学杂志

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the activity and expression of Ca(2+)-Mg(2+)-ATPase in irradiated rat masseter muscle.</p><p><b>METHODS</b>The rats were irradiated locally with a single dose of 20 Gy X-ray. The activities of Ca(2+)-Mg(2+)-ATPase were measured with colorimetric method. The protein expression of Ca(2+)-Mg(2+)-ATPase was determined by Western blotting and immunohistochemistry.</p><p><b>RESULTS</b>The activities of Ca(2+)-Mg(2+)-ATPase in masseter muscle decreased by approximately 20% and 40% in irradiated rats on days 3 and 30 postirradiation. There was significant difference in the expression of Ca(2+)-Mg(2+)-ATPase protein between irradiated and nonirradiated rats on day 30 postirradiation. Ca(2+)-Mg(2+)-ATPase protein was found in the cytoplasm of masseter muscle.</p><p><b>CONCLUSIONS</b>The decrease of ATPase activity played an important role in the cause of radiation-induced skeletal muscle injury, while there was no significant reduction in the expression of Ca(2+)-Mg(2+)-ATPase protein in irradiated rat masseter muscle.</p>