Abstract
The involvement of a hypocalcemic hormone calcitonin (CT) in the expression of hepatic Ca2+-binding protein regucalcin mRNA was investigated. The change of regucalcin mRNA levels was analyzed by Northern blotting using liver regucalcin complementary DNA (0.9 kb). A single oral administration of calcium chloride (100 mg Ca/100 g body weight) to rats induced a remarkable increase in the serum calcium concentration and a corresponding elevation of the liver calcium content during 120 min after the administration. Thyroparathyroidectomy (TPTX) did not cause a significant increase in the liver calcium content after calcium administration. Hepatic regucalcin mRNA level was markedly elevated by calcium administration; the level was about 180% of controls at 60 min after the administration. This increase was completely abolished by TPTX. A single subcutaneous administration of CT (synthetic eel CT; 25–100 MRC mU/100 g) to TPTX rats received oral administration of calcium (100 mg/100 g) produced a remarkable increase in hepatic regucalcin mRNA levels; the level was about 280% of controls with the dose of 25 MRC mU CT/100 g. The present finding suggests that the expression of hepatic mRNA is stimulated by CT, and that the hormonal effect is mediated through Ca2+ in rat liver.
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Yamaguchi, M., Kanayama, Y. & Shimokawa, N. Expression of calcium-binding protein regucalcin mRNA in rat liver is stimulated by calcitonin: The hormonal effect is mediated through calcium. Mol Cell Biochem 136, 43–48 (1994). https://doi.org/10.1007/BF00931603
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DOI: https://doi.org/10.1007/BF00931603