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

Barbiturates block divalent cation action potentials in leech nociceptive cells.

J Johansen, A L Kleinhaus

    Brain Research
    |June 25, 1986
    PubMed
    Summary
    This summary is machine-generated.

    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

    Improved quantum processor logical error rates via correction and detection.

    Nature·2026
    Same author

    Radiotherapy quality assurance of patients with squamous cell carcinoma of the head and neck included in the DAHANCA 19 randomised phase III trial.

    Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology·2025
    Same author

    High-fidelity teleportation of a logical qubit using transversal gates and lattice surgery.

    Science (New York, N.Y.)·2024
    Same author

    Acute toxicities in proton therapy for head and neck cancer - A matched analysis of the DAHANCA 35 feasibility study.

    Clinical and translational radiation oncology·2024
    Same author

    Considerations for study design in the DAHANCA 35 trial of protons versus photons for head and neck cancer.

    Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology·2023
    Same author

    Late toxicity in the brain after radiotherapy for sinonasal cancer: Neurocognitive functioning, MRI of the brain and quality of life.

    Clinical and translational radiation oncology·2020

    Barbiturates like phenobarbital, pentobarbital, and methohexital affect leech neuron action potentials by reducing depolarization rate and duration. Their potency suggests the non-ionized drug form is active in these invertebrate neurons.

    Area of Science:

    • Neuroscience
    • Pharmacology
    • Electrophysiology

    Background:

    • Barbiturates are known for their effects on neuronal excitability.
    • Leeches possess nociceptive neurons with distinct pharmacological properties.
    • Divalent cations can support action potentials in the absence of sodium.

    Purpose of the Study:

    • To investigate the effects of phenobarbital, pentobarbital, and methohexital on leech nociceptive neuron action potentials.
    • To determine the dose-dependency and reversibility of barbiturate actions.
    • To explore potential differences in barbiturate sensitivity between leech neuron subtypes.

    Main Methods:

    • Electrophysiological recordings of leech nociceptive neurons in sodium-free solutions.
    • Application of tetraethylammonium (TEA) to block potassium channels.

    Related Experiment Videos

  • Dose-response analysis to determine ED50 values for barbiturate effects on Vmax.
  • Experiments in sodium-containing Ringer to assess effects on resting membrane potential and resistance.

    • Main Results:

    • Phenobarbital, pentobarbital, and methohexital decreased Vmax and duration of divalent cation action potentials in a dose-dependent and reversible manner.
    • The order of potency (methohexital > pentobarbital > phenobarbital) correlated with the non-ionized fraction of the drugs at physiological pH.
    • Barbiturates depolarized lateral nociceptive cells and decreased their membrane resistance in sodium-containing solutions, but not medial nociceptive cells.

    Conclusions:

    • The non-ionized form of barbiturates is likely the active species in leech nociceptive neurons.
    • These findings highlight pharmacological distinctions between closely related leech neuron types.
    • Barbiturate-induced membrane actions may contribute to their known excitatory effects in various preparations.