Abstract
Addition of crosslinking antibody to B lymphocytes results in a rapid rise in cytoplasmic-free Ca2+ ([Ca2+]i) due to release of Ca2+ from internal stores and uptake of Ca2+ across the plasma membrane. Inositol 1,4,5-trisphosphate is believed to mediate the release of internal Ca2+ stores and has also been proposed to mediate extracellular Ca2+ entry. We have compared the properties of these two pathways for Ca2+ mobilization by dissociating the [Ca2+]i changes in ligand-activated human B cells after loading of the cells with the Ca2+ chelator BAPTA. In the present paper we show that: (a) the sustained increase in [Ca2+]i is due to increased unidirectional influx of external [Ca2+]i; (b) entry of extracellular Ca2+, but not release of internal stores, is sensitive to the transmembrane potential; and (c) entry of extracellular Ca2+, but not release of internal stores, is inhibited by increasing [Ca2+]i. These findings suggest that the permeation pathways mediating the translocation of Ca2+ across the plasma membrane and endoplasmic reticulum membrane are not identical.
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Selected References
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- Berridge M. J. Inositol trisphosphate and diacylglycerol as second messengers. Biochem J. 1984 Jun 1;220(2):345–360. doi: 10.1042/bj2200345. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Berridge M. J., Irvine R. F. Inositol trisphosphate, a novel second messenger in cellular signal transduction. Nature. 1984 Nov 22;312(5992):315–321. doi: 10.1038/312315a0. [DOI] [PubMed] [Google Scholar]
- Bijsterbosch M. K., Rigley K. P., Klaus G. G. Cross-linking of surface immunoglobulin on B lymphocytes induces both intracellular Ca2+ release and Ca2+ influx: analysis with indo-1. Biochem Biophys Res Commun. 1986 May 29;137(1):500–506. doi: 10.1016/0006-291x(86)91238-6. [DOI] [PubMed] [Google Scholar]
- Cheung R. K., Grinstein S., Gelfand E. W. Volume regulation by human lymphocytes. Identification of differences between the two major lymphocyte subpopulations. J Clin Invest. 1982 Sep;70(3):632–638. doi: 10.1172/JCI110657. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gelfand E. W., Cheung R. K., Grinstein S. Mitogen-induced changes in Ca2+ permeability are not mediated by voltage-gated K+ channels. J Biol Chem. 1986 Sep 5;261(25):11520–11523. [PubMed] [Google Scholar]
- Irvine R. F., Moor R. M. Micro-injection of inositol 1,3,4,5-tetrakisphosphate activates sea urchin eggs by a mechanism dependent on external Ca2+. Biochem J. 1986 Dec 15;240(3):917–920. doi: 10.1042/bj2400917. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ishida Y., Chused T. M. Heterogeneity of lymphocyte calcium metabolism is caused by T cell-specific calcium-sensitive potassium channel and sensitivity of the calcium ATPase pump to membrane potential. J Exp Med. 1988 Sep 1;168(3):839–852. doi: 10.1084/jem.168.3.839. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kuno M., Gardner P. Ion channels activated by inositol 1,4,5-trisphosphate in plasma membrane of human T-lymphocytes. Nature. 1987 Mar 19;326(6110):301–304. doi: 10.1038/326301a0. [DOI] [PubMed] [Google Scholar]
- Kuno M., Goronzy J., Weyand C. M., Gardner P. Single-channel and whole-cell recordings of mitogen-regulated inward currents in human cloned helper T lymphocytes. Nature. 1986 Sep 18;323(6085):269–273. doi: 10.1038/323269a0. [DOI] [PubMed] [Google Scholar]
- MacDougall S. L., Grinstein S., Gelfand E. W. Activation of Ca2+-dependent K+ channels in human B lymphocytes by anti-immunoglobulin. J Clin Invest. 1988 Feb;81(2):449–454. doi: 10.1172/JCI113340. [DOI] [PMC free article] [PubMed] [Google Scholar]
- MacDougall S. L., Grinstein S., Gelfand E. W. Detection of ligand-activated conductive Ca2+ channels in human B lymphocytes. Cell. 1988 Jul 15;54(2):229–234. doi: 10.1016/0092-8674(88)90555-7. [DOI] [PubMed] [Google Scholar]
- Nishizuka Y. The role of protein kinase C in cell surface signal transduction and tumour promotion. Nature. 1984 Apr 19;308(5961):693–698. doi: 10.1038/308693a0. [DOI] [PubMed] [Google Scholar]
- Putney J. W., Jr A model for receptor-regulated calcium entry. Cell Calcium. 1986 Feb;7(1):1–12. doi: 10.1016/0143-4160(86)90026-6. [DOI] [PubMed] [Google Scholar]
- von Tscharner V., Prod'hom B., Baggiolini M., Reuter H. Ion channels in human neutrophils activated by a rise in free cytosolic calcium concentration. 1986 Nov 27-Dec 3Nature. 324(6095):369–372. doi: 10.1038/324369a0. [DOI] [PubMed] [Google Scholar]