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

The University of Texas System (UT)

Status: Completed

Conditions: Pain

Study type: Observational

Funder types: Other; NIH

Identifiers

NCT00223366

HSC20020071H

R01NS058655 (U.S. NIH Grant/Contract)

Details and patient eligibility

About

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

Full description

Purpose/Objectives

a. 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.

Enrollment: 2,007 patients

Sex: All

Ages: 16 to 90 years old

Volunteers: Accepts Healthy Volunteers

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.