Affordable Access

Publisher Website

Cyclic AMP-mediated stimulation by calcium of thymocyte proliferation

Authors
Journal
Experimental Cell Research
0014-4827
Publisher
Elsevier
Publication Date
Volume
69
Issue
2
Identifiers
DOI: 10.1016/0014-4827(71)90225-4
Disciplines
  • Biology

Abstract

Abstract Varying the extracellular calcium concentration between 0 and 1.0 mM does not affect the proliferation of rat thymocytes maintained in vitro. However, higher calcium concentrations raise the level of cell proliferation and increase the intracellular concentration of cyclic AMP. Calcium's mitogenic action is inhibited by imidazole, a compound which increases the activity of the cyclic AMP-degrading enzyme phosphodiesterase and thereby also prevents calcium from increasing the cellular cyclic AMP content. Caffeine, which inhibits phosphodiesterase activity, sensitizes thymocytes to the mitogenic action of calcium. Caffeine can also stimulate thymocyte proliferation by itself and, like calcium, causes a significant rise in the cellular cyclic AMP content. Mitogenic levels of calcium, in turn, act like caffeine and reduce the activity of cyclic AMP-phosphodiesterase. These observations combine to suggest that calcium is the physiological equivalent of caffeine and exerts its effect on thymocyte proliferation by reducing the activity of cyclic AMP-phosphodiesterase.

There are no comments yet on this publication. Be the first to share your thoughts.

Statistics

Seen <100 times
0 Comments

More articles like this

Cyclic AMP-mediated stimulation by calcium of thym...

on Experimental Cell Research December 1971

Calcium-mediated effects of cyclic GMP on the stim...

on Proceedings of the Society for... March 1972

Inhibition by thyrocalcitonin (calcitonin) of the...

on Hormone and metabolic research... September 1971

Cyclic AMP-mediated stimulation of thymocyte proli...

on Proceedings of the Society for... September 1970
More articles like this..