A Mechanistic Evaluation of the Interactions Between Thermoceptive and Pruriceptive Sensory Processing

En Mekanistisk undersøgelse af Interaktioner Imellem Det Thermoceptive og Det Pruriceptive Sensoriske System

The purpose of this human experimental study is to evaluate the pattern of itch intensity over time in response to strong, short-term heat stimulation in two different models of histamine and cowhage-induced itch. Moreover, the purpose is to evaluate the effect of mild pre-heating of the skin in human experimental models of histamine, cowhage and serotonin. Finally, we want to investigate the effect of short-term intense heat stimulation on previously anesthetized skin.

Study Overview

• Status: Completed
• Conditions: Itch; Histamine; Cowhage; Thermal Stimulation; Serotonine
• Intervention / Treatment: Other: Histamine; Other: Cowhage; Other: Heat stimulation; Other: Pre-heating; Other: Serotonin; Drug: Lidocaine

• Study Type: Interventional
• Enrollment (Actual): 59
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Denmark
  • Nordjylland
    • Aalborg, Nordjylland, Denmark, 9220
      • Aalborg University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 60 years (ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Healthy men and women
• Age 18-60 years
• Able to speak and understand English

Exclusion Criteria:

• Suffering from chronic disease
• Pregnancy or lactation
• Prior experience of adverse effects from anaesthetic, specifically Lidocaine
• Drug addiction defined as the use of cannabis, opioids or other drugs - 5 -
• Previous neurologic, musculoskeletal or mental illnesses
• Lack of ability to cooperate
• Current use of medications that may affect the trial
• Active skin diseases
• Active participation in other experiments currently ongoing or within the last 14 days
• Tattoos on volar forearms that will interfere with local skin measurements

Study Plan

How is the study designed?

Design Details

• Primary Purpose: BASIC_SCIENCE
• Allocation: RANDOMIZED
• Interventional Model: CROSSOVER
• Masking: DOUBLE

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Histamine+cowhage+heat	Other: Histamine; Skin Prick Test with Histamine; Other: Cowhage; Manually skin insertion of cowhage spicules; Other: Heat stimulation; Short heat stimulation
EXPERIMENTAL: Histamine+cowhage+serotonin+pre-heating	Other: Histamine; Skin Prick Test with Histamine; Other: Cowhage; Manually skin insertion of cowhage spicules; Other: Pre-heating; Mild skin pre-heating; Other: Serotonin; Serotonin electrophoresis
PLACEBO_COMPARATOR: lidocaine and saline+heat	Other: Heat stimulation; Short heat stimulation; Drug: Lidocaine; Lidocaine intradermal injection

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
eVAS Itch	Electronic Visual Analog Scale for itch sensation. 0-100 scale, it measures the self-estimated itch the subject experience on a scale where 0 correspond to "No itch" and 100 "Worst itch imaginable".	10 minutes
Skin temperature	Infrared skin thermometer	5 seconds
eVAS Pain	Electronic Visual Analog Scale for pain sensation. 0-100 scale, it measures the self-estimated pain the subject experience on a scale where 0 correspond to "No pain" and 100 "Worst pain imaginable".	10 minutes

Collaborators and Investigators

• Sponsor: Aalborg University
• Investigators: Principal Investigator: Daniele Riccio, MSc, Aalborg University

Study record dates

Study Major Dates

• Study Start (ACTUAL): July 1, 2018
• Primary Completion (ACTUAL): July 31, 2019
• Study Completion (ACTUAL): August 28, 2019

Study Registration Dates

• First Submitted: June 22, 2018
• First Submitted That Met QC Criteria: June 22, 2018
• First Posted (ACTUAL): July 3, 2018

Study Record Updates

• Last Update Posted (ACTUAL): July 8, 2020
• Last Update Submitted That Met QC Criteria: July 7, 2020
• Last Verified: July 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Anti-Arrhythmia Agents; Central Nervous System Depressants; Peripheral Nervous System Agents; Sensory System Agents; Anesthetics; Membrane Transport Modulators; Serotonin Agents; Serotonin Receptor Agonists; Anesthetics, Local; Voltage-Gated Sodium Channel Blockers; Sodium Channel Blockers; Histamine Agents; Histamine Agonists; Lidocaine; Serotonin; Histamine
• Other Study ID Numbers: N-20180035

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No