Effect of pteridine derivatives on intracellular calcium concentration in human monocytic cells

FEBS Letters

Lang, F.¹  Fuchs, D.³  Wöll, E.²  Wachter, H.³  Weiss, G.³ 

[1] Department for Physiology, University of Tübingen, Tübingen, Germany;Department for Physiology, University of Innsbruck, Innsbruck, Austria;Institute for Medical Chemistry and Biochemistry, University of Innsbruck, Innsbruck, Austria

关键词: Intracellular calcium;    Macrophage;    Neopterin;    Tetrahydrobiopterin;    Lanthanum;   

DOI  :  10.1016/0014-5793(93)80522-V

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Pteridines are heterocyclic compounds which are synthesized and released by human monocytes/macrophages following stimulation by interferonγ. Their concentration in various body fluids proved to be indicative for the stimulation of the cellular immune system, and determination of pteridines has become an important diagnostic tool. We show that pteridine derivatives, namely neopterin (N), 7,8-dihydroneopterin (NH₂), and 5,6,7,8-tetrahydrobiopterin (BH₄) increase intracellular calcium (Ca_i) in human monocytic cells. Significant increases of Ca_i, are observed at 10 nmol/l NH₂, at 100 nmol/l BH4 and at 1 mol/l N, i.e. at concentrations encountered in vivo. At a concentration of 1 μmol/l, Ca_i is increased (from a control value of 145 ± 7 nmol/l) to 464 ± 62 nmol/l (NH₂), 340 ± 41 nmol/l (BH₄) and 344 ± 46 nmol/l (N), respectively. The increase of Ca_i depends on the presence of extracellular calcium and is likely to be due to activation of a calcium channel. We show that the absence of extracellular calcium or the addition of lanthanum ions to the extracellular fluid fully reverses the pteridine-induced increase of Ca_i. According to these observations, pteridines may mimick the effects of other inflammatory mediators on monocytic cells and seem to be involved in the crosstalk of immunocompetent cells.

【 授权许可】

Unknown