Diurnal fluctuations in calcium level in the blood serum and homogenates of the kidney and small intestine of mice. II. Influence of UV-rays
Fiałkowska, M.
Folia Biologica 28(3): 287-299
1980
ISSN/ISBN: 0015-5497 PMID: 7192652 Document Number: 159653
Male and female mice were whole-body exposed for 1 h to UV-radiation of 245-405 nm wave-length and rhythmic changes in the Ca level in the blood serum and renal and intestinal homogenates were studied at 6 h intervals in the course of 1 day (i.e., at 12.00, 18.00, 24.00, 6.00 and 12.00 h). In the control mice the Ca level in the blood serum and homogenates of the small intestine and kidney showed distinct variations. The level was changed in the mice irradiated with UV rays of 245-405 nm wavelength. The dose of UV radiation applied apparently enhanced synthesis of biologically active metabolites of vitamin D. An excess of vitamin D then directly influenced the rhythm of Ca absorption by the intestinal epithelium and reabsorption in the renal tubules. Since the intestine and kidneys were responsible for Ca homeostasis, rhythmicity of the serum Ca level was affected.