In Vitro Studies on Pharmacological Regulation and Genetic Risk Factors of Peripheral Human Nociceptors

Sponsor
The University of Texas Health Science Center at San Antonio (Other)
Overall Status
Completed
CT.gov ID
NCT00223366
Collaborator
National Institutes of Health (NIH) (NIH), National Institute of Neurological Disorders and Stroke (NINDS) (NIH)
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Study Details

Study Description

Brief Summary

This protocol is for a number of in vitro studies using human surgical biopsies and evaluating the pharmacology and genetics of human nociceptors ("pain detecting") neurons

Condition or Disease Intervention/Treatment Phase

    Detailed Description

    Purpose/Objectives

    1. Specific Aims Specific Aim 1: Characterize in humans the effects of inflammation and neuronal degeneration on peripheral levels of NPY, and related Y receptors (Y1, Y2, Y5) in periradicular tissue.

    Specific Aim 2: Determine whether NPY inhibits neurosecretion from peripheral terminals of capsaicin-sensitive neurons innervating normal versus inflamed tissue.

    Specific Aim 3: Determine whether peripheral administration of NPY is analgesic and/or anti-allodynic in patients experiencing spontaneous pain and mechanical allodynia in a clinical model of inflammation with associated neuronal degeneration.

    Specific Aim 4: Evaluate whether population characteristics are associated with altered pain reports. First, we will determine whether patients with the C1128 single nucleotide polymorphism (SNP) of the PreProNPY gene, whose phenotype confers substantially augmented peripheral NPY neurosecretion, report less pain compared with patients without this genetic polymorphism. Second, we will determine whether ethnic/cultural factors associated with an underserved minority population (Hispanics in the San Antonio area) are associated with altered pain reports.

    Study Design

    Study Type:
    Observational
    Actual Enrollment :
    2007 participants
    Observational Model:
    Case-Only
    Time Perspective:
    Cross-Sectional
    Official Title:
    Studies on Normal and Inflamed Dental Pulp, NPY Regulation of Peripheral Human Nociceptors, Peripheral Mechanisms of Opioid Analgesia, Cannabinoid-induced Desensitization of TRPV1 Receptors Adrenergic Modulation of Trigeminal Nociceptors
    Actual Study Start Date :
    Oct 1, 2001
    Actual Primary Completion Date :
    May 19, 2019
    Actual Study Completion Date :
    May 19, 2019

    Outcome Measures

    Primary Outcome Measures

    1. Effects of inflammation in periradicular tissues. [Immediately following tooth extraction and dental pulp procurement.]

      Extracted human teeth are sectioned to obtain the crown dental pulp which is placed in a well plate. The pulp is moved every twenty minutes through proprietary substances for a total of 60 to 120 minutes depending on the specific experiment. After each 20 minute fraction, the buffer solution in each well plate is collected, labeled and placed in the -80 freezer along with the pulp sample.

    Secondary Outcome Measures

    1. Altered pain reports. [24 hour post-tooth extraction.]

      Patients provide perceived pain within the first 24 hours post-extraction via a take-home pain postcard. The postcard has a Visual Analog Scale pain graft that the patient marks and returns via mail.

    Eligibility Criteria

    Criteria

    Ages Eligible for Study:
    16 Years to 90 Years
    Sexes Eligible for Study:
    All
    Accepts Healthy Volunteers:
    Yes
    Inclusion Criteria:
    • Willingness to participate; identified indication to have a tooth extraction; 16-90 years old; diagnosis of normal pulp; or diagnosis of irreversible pulpitis requiring a symptom of spontaneous pain and positive and lingering response to pulp vitality test.
    Exclusion Criteria:
    • History of taking steroids within the last month; history of taking analgesics in the last four hours.

    Contacts and Locations

    Locations

    Site City State Country Postal Code
    1 The University of Texas Health Science Center at San Antonio San Antonio Texas United States 78229

    Sponsors and Collaborators

    • The University of Texas Health Science Center at San Antonio
    • National Institutes of Health (NIH)
    • National Institute of Neurological Disorders and Stroke (NINDS)

    Investigators

    • Principal Investigator: Kenneth M. Hargreaves, DDS, PhD, University of Texas Health Science Center at San Antonio, Texas

    Study Documents (Full-Text)

    None provided.

    More Information

    Publications

    None provided.
    Responsible Party:
    Kenneth Hargreaves, Chair, Dept. of Endodontics, The University of Texas Health Science Center at San Antonio
    ClinicalTrials.gov Identifier:
    NCT00223366
    Other Study ID Numbers:
    • HSC20020071H
    • R01NS058655
    First Posted:
    Sep 22, 2005
    Last Update Posted:
    Nov 3, 2020
    Last Verified:
    Nov 1, 2020
    Keywords provided by Kenneth Hargreaves, Chair, Dept. of Endodontics, The University of Texas Health Science Center at San Antonio

    Study Results

    No Results Posted as of Nov 3, 2020