Adenosine P1 purinoreceptors modulate the cholinoreceptors-mediated intracellular calcium signalling in the acinar cells of submandibular salivary gland
Abstract
The physiological relevance of the adenosine receptors in the functioning of salivary gland acinar cells still remains unclear. Using fluorescent calcium dye fura-2/AM we carried out the measurements of intracellular free calcium concentration ([Ca2+]i) in the acinar cells from submandibular salivary gland during the activation of adenosine receptors. We have found that adenosine itself has no effect on the [Ca2+]i in submandibular cells, although it was able to potentiates acetylcholine- and carbacholine-induced [Ca2+]i transients. Besides, the ability of adenosine to potentiate [Ca2+]i transients was observed only when agonist was used in concentrations less than sub-maximal. We conclude that functioning adenosine receptors are present in the submandibular acinar cells and their activation lead to alteration in the phospholipase C - InsP3 signaling pathway instead of directly affecting intracellular calcium signaling. Adenosine-induced potentiation of [Ca2+]i transients observed upon activation of choline receptors could be due to phosphorylation of InsP3-receptors by cAMP-dependent protein kinases.
Downloads
References
P. 4 — 25.
2. Bucheimer R.E., Linden J. Purinergic regulation of epithelial transport // J. Physiol. 2004. 555. Pt 2. P. 311 - 321.
3. Burnstock G., Knight G.E. Cellular distribution and functions of P2 receptor subtypes in different systems // Int. Rev. Cytol. 2004. 240. P. 31 - 304.
4. Cobb B.R., Ruiz P., King CM., Fortenberry J. Et al. A (2) adenosine receptors regulate CFTR through PKA and PLA (2) // Am. J. Physiol. Lung Cell Mol. Physiol. 2002. 282, № 1. P. 12- 25.
5. Evellin S., Nolte J., Tysack K. et al. Stimulation of phospholipase C-epsilon by the M3 muscarinic acetylcholine receptor-mediated by cyclic AMP and the GTPase Rap2B // J. Biol. Chem. 2002. 277, №19. P. 16805 - 168013.
6. Fedirko N., Vats Ju., Klevets M., Kruglikov I., Voitenko. N. Neuronal control of the exocytosis and calcium homeostasis //Neurophysiology. 2002. P. 144-147.
7. Feoktistov I., Biaggioni I. Adenosine A2B receptors // Pharmacol. Rev. 1997. 49, № 4. P. 381 - 402.
8. Gallacher D.V. Are there purinergic receptors on parotid acinar cells? // Nature. 1982. 296, № 5852. P. 83 - 86.
9. Grynkiewicz G., Poenie M., Tsien R.Y. A new generation of Ca2+ indicators with greatly improved fluorescence properties // J. Biol. Chem. 1985. 260, № 6. P. 3440 - 3450.
10. Linden J., Thai T., Figler H., Jin X., Robeva A.S. Characterization of human A(2B) adenosine receptors: radioligand binding, western blotting, and coupling to G(q) in human embryonic kidney 293 cells and HMC-1 mast cells // Mol. Pharmacol. 1999. 56, № 4. P. 705 - 713.
11. Ralevic V., Burnstock G. Receptors for purines and pyrimidines // Pharmacol. Rev. 1998. 50, № 3. P. 413-492.
12. Reshkin S.J., Guerra L., Bagorda A. et al. Activation of A (3) adenosine receptor induces calcium entry and chloride secretion in A (6) cells // J. Membr. Biol. 2000. 178, №2. P. 103-113.
13. Sitaraman S.V., Wang L., Wong M. et al. The adenosine 2b receptor is recruited to the plasma membrane and associates with E3KARP and Ezrin upon agonist stimulation // J. Biol. Chem. 2002. 277, №36. P. 33188 - 33195.
14. Turner J.T., Landon L.A, Gibbons S.J., Talamo B.R. Salivary gland P2 nucleotide receptors // Crit. Rev. Oral. Biol. Med. 1999. 10, № 2. P. 210-224.
15. Vats J.A, Fedirko N.V , Klevets M.Y. et al. Role of SH Groups in the Functioning of Са2+-Transporting ATPases Regulating Са2+ Homeostasis and Exocytosis //Neurophysiology. 2002. 34, №1. P. 5 - 12.
16. Zhang G. H., Martinez J.R., Effects of forskolin, dibutyryl cAMP and H89 on Ca2' mobilization in the submandibular salivary cell of newborn rats//Arch Oral. Biol. 1999. 44, № 9. P. 735 - 744.
17. Wagner L.E, Li W.H., Yule D.I. Phosphorylation of type-1 inositol 1,4,5-trisphosphate receptors by cyclic nucleotide-dependent protein kinases a mutational analysis of the functionally important sites in the S 2+ and S2- splice variants // J. Biol. Chem. 2003.278. №46. P. 45811 - 45817.
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).
