Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Calcium binding to intestinal membranes.

J L Oschman, B J Wall

    The Journal of Cell Biology
    |October 1, 1972
    PubMed
    Summary
    This summary is machine-generated.

    Calcium in routine electron microscopy fixatives causes electron-opaque deposits near cell membranes. This artifact, particularly in insect midgut, mimics ion localization techniques and highlights calcium

    Related Concept Videos

    You might also read

    Related Articles

    Articles linked to this work by shared authors, journal, and citation graph.

    Sort by
    Same author

    STRUCTURE AND REPRODUCTION OF THE ALGAL SYMBIONTS OF HYDRA VIRIDIS(1).

    Journal of phycology·2016
    Same author

    DEVELOPMENT OF THE SYMBIOSIS OF CONVOLUTA ROSCOFFENSIS GRAFF AND PLATYMONAS SP.(1).

    Journal of phycology·2016
    Same author

    Mechanism and control of fluid secretion.

    The Yale journal of biology and medicine·1977
    Same author

    Morphology and function of Malpighian tubules and associated structures in the cockroach, Periplaneta americana.

    Journal of morphology·1975
    Same author

    Association of calcium with membranes of squid giant axon: ultrastructure and microprobe analysis.

    The Journal of cell biology·1974
    Same author

    Fluid transport: concentration of the intercellular compartment.

    Science (New York, N.Y.)·1970
    Same journal

    Synergistic assembly, disassembly, and protection of complex forms of bundled F-actin.

    The Journal of cell biology·2026
    Same journal

    Recruitment and release of XPG during NER is controlled by pre- and post-incision factors and EXO1.

    The Journal of cell biology·2026
    Same journal

    Meiotic CENP-C supports centromere assembly and kinetochore recruitment in spermatogenesis.

    The Journal of cell biology·2026
    Same journal

    Phosphatidylserine and RhoB connect PI4P and PA metabolism to maintain plasma membrane identity.

    The Journal of cell biology·2026
    Same journal

    PIKfyve influences inter-organelle contacts with lysosomes to modulate the endoplasmic reticulum.

    The Journal of cell biology·2026
    Same journal

    Sequential changes in calcium transients during M phase regulate cardiomyocyte proliferation.

    The Journal of cell biology·2026
    See all related articles

    Area of Science:

    • Cell Biology
    • Microscopy Techniques
    • Biochemistry

    Background:

    • Routine electron microscopy fixatives, such as glutaraldehyde and buffer solutions, often contain calcium.
    • Calcium presence in fixatives can lead to the formation of electron-opaque deposits adjacent to cellular membranes.
    • These deposits can be mistaken for specific ion localizations, potentially confounding experimental results.

    Purpose of the Study:

    • To investigate the origin and nature of electron-opaque deposits observed in tissues prepared for electron microscopy.
    • To determine the role of calcium in the formation of these deposits.
    • To clarify the implications of calcium-induced artifacts for ion localization studies.

    Main Methods:

    • Flame photometry was used to quantify calcium levels in glutaraldehyde and buffer solutions.

    Related Experiment Videos

  • Various tissues, including insect intestine, were fixed using solutions with and without calcium.
  • Electron microscopy was employed to visualize cellular structures and deposits, with and without post-fixation treatments and varying ion concentrations.

    • Main Results:

    • Calcium was detected in commonly used electron microscopy fixatives.
    • Electron-opaque deposits adjacent to plasma membranes, particularly in insect midgut, correlated directly with the presence of calcium in fixatives.
    • These deposits were observed even with trace amounts of calcium (as low as 5 x 10(-5)M) and could be mimicked by other divalent cations (Mg++, Sr++, Ba++, Mn++, Fe++), but not monovalent ions.
    • Deposits appeared along junctional membranes and, after specific postfixation, resolved to the inner leaflet of apical and lateral plasma membranes, suggesting localization of calcium-binding membrane constituents.

    Conclusions:

    • Calcium contamination in electron microscopy fixatives is a common source of artifactual electron-opaque deposits.
    • These calcium-induced deposits can be misinterpreted as specific ion localizations, impacting studies on ion transport and cell communication.
    • Careful control of calcium levels in fixatives and wash solutions is crucial for accurate ultrastructural and ion localization studies.