These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Effects of extracellular Ca++ and Mg++ on cytosolic Ca++ and PTH release in dispersed bovine parathyroid cells. Author: Shoback D, Thatcher J, Leombruno R, Brown E. Journal: Endocrinology; 1983 Jul; 113(1):424-6. PubMed ID: 6861713. Abstract: We studied the effects of varying extracellular concentrations of Ca++ and Mg++ on cytosolic Ca++ concentration and PTH release by incorporating the Ca++-sensitive, fluorescent dye "QUIN 2" into dispersed bovine parathyroid cells. Increasing extracellular Ca++ from 0.5 to 2.0 mM led to a dose-dependent increase in cytosolic Ca++ from 179 +/- 8 to 646 +/- 68 nM (mean +/- SE, N = 13; P less than 0.01), which correlated closely (r = -.987, P less than .001) with the suppression of PTH secretion by the same Ca++ concentrations. Raising extracellular Mg++ from 0.5 to 3 mM also caused a dose-related increase in cytosolic Ca++ from 176 +/- 10 to 277 +/- 15 nM (N = 12, P less than 0.01) which correlated (r = -.959, P less than .01) with inhibition of PTH release. These results show a close inverse relationship between cytosolic Ca++ and PTH release with alterations in extracellular Ca++ or Mg++. Cytosolic Ca++ may, therefore, act as a second messenger mediating the effects of these divalent cations on PTH release.[Abstract] [Full Text] [Related] [New Search]