October 1992
Volume 33, Issue 11
Free
Articles  |   October 1992
Histamine H1 receptor-mediated Ca2+ signaling in cultured bovine corneal endothelial cells.
Author Affiliations
  • K M Crawford
    Department of Anatomy and Cell Biology, University of Michigan, Ann Arbor 48109-0616.
  • D K MacCallum
    Department of Anatomy and Cell Biology, University of Michigan, Ann Arbor 48109-0616.
  • S A Ernst
    Department of Anatomy and Cell Biology, University of Michigan, Ann Arbor 48109-0616.
Investigative Ophthalmology & Visual Science October 1992, Vol.33, 3041-3049. doi:
  • Views
  • PDF
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      K M Crawford, D K MacCallum, S A Ernst; Histamine H1 receptor-mediated Ca2+ signaling in cultured bovine corneal endothelial cells.. Invest. Ophthalmol. Vis. Sci. 1992;33(11):3041-3049.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

The corneal endothelium pumps ions and water from the stroma to the aqueous humor, maintaining corneal transparency. This report investigates the possibility that cultured corneal endothelial cells express neurohormonal Ca2+ signaling pathways employed by other epithelia to regulate transport or other cellular functions. Agonist-stimulated changes in intracellular calcium ([Ca2+]i) in single bovine corneal endothelial cells (BCEC) derived from confluent cultures were measured by microspectrofluorimetry using the Ca(2+)-sensitive probe, fura 2. Mean resting [Ca2+]i in BCEC was 46 +/- 2 nM (n = 124). The muscarinic cholinergic agonist, carbachol, did not mobilize Ca2+, whereas histamine induced a rapid increase in [Ca2+]i to initial peak levels of 549 +/- 22 nM (n = 46) at maximally stimulating doses. The initial rise in [Ca2+]i in response to histamine was dose dependent, with a minimum effective dose of 50 nM, EC50 = 0.84 mumol/l, and a maximum effective dose of 10 mumol/l. [Ca2+]i decreased from the initial peak, but then stabilized to form an agonist-dependent sustained elevation or abruptly fell back to baseline to begin oscillatory fluctuations. The initial peak was insensitive to removal of extracellular calcium (Ca2+o), whereas subsequent elevations in [Ca2+]i or sustained [Ca2+]i oscillations required Ca2+o. The amplitude of the oscillations in [Ca2+]i increased with an increase in [histamine]. However, frequency was independent of [histamine] (mean = 0.62 spikes min-1 +/- 0.06, n = 33). Histamine-induced Ca2+ mobilization was inhibited by the H1 receptor antagonist triprolidine, but was unaffected by ranitidine (H2 antagonist) or thioperamide (H3 antagonist).(ABSTRACT TRUNCATED AT 250 WORDS)

×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×