Effects of Anticipation of Pain Relief on Brain Mechanisms

Pain Clinical Trial

Official title:

Neurochemical Mediation of Placebo Responses in Humans

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00200876
• Other study ID #: R01AT001415-01A1
• Secondary ID: R01AT001415-01A1
• Status: Completed
• Phase: N/A
• First received: September 13, 2005
• Last updated: March 21, 2017
• Start date: September 2003
• Est. completion date: June 2008

Study information

• Verified date: March 2017
• Source: University of Michigan
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

This study will use brain imaging technology to examine chemical systems in the brain that suppress pain and stress when an individual has an expectation of pain relief.

Description:

Evidence suggests that the expectation of pain relief, even if a person receives only a placebo, can provide actual therapeutic benefits. The µ-opioid receptor system, located in the brain, is activated during anticipation of pain relief; this activation suppresses stress and pain responses. This study will use brain imaging technology to examine the effects of a placebo intervention on µ-opioid neurotransmitters. Examination of the factors that regulate these placebo-activated neurotransmitter responses will clarify the overall neurobiology underlying variations in the responses to placebos, as well as pain and other stressful conditions, ultimately leading to the optimization of medical and psychological interventions.

This study will last several hours during one study visit. Participants will receive both a painful and a painless injection while undergoing positron emission tomography (PET) brain imaging. The painful injection will consist of small amounts of hypertoninc saline (concentrated saline that causes cell shrinkage) in the jaw muscle over a 20-minute period. Several minutes after participants receive hypertonic saline, they will receive an injection with isotonic saline not associated with pain in the opposite jaw muscle. After participants receive the injections, they will either be told or not be told about a pain relief intervention. PET imaging will continue as participants either anticipate or do not anticipate pain relief. Participants will be asked about their pain levels repeatedly throughout the study; their responses will be entered into a computer-controlled system which will modulate rates of saline infusion.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 60
• Est. completion date: June 2008
• Est. primary completion date: February 2008
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 20 Years to 30 Years

Eligibility

Inclusion Criteria:

• Willing and able to comply with all study requirements

Exclusion Criteria:

• Presence of pain at study entry

• Personal or first-degree (e.g., mother, father, sister, brother) family history of neurologic or psychiatric disorders

• History of substance abuse or dependence

• Left-handed or ambidextrous

• Positive urine toxicology screen

• Acute or uncorrected medical illness that may interfere with the study

• Unable to tolerate brain scanning procedures

• Current treatment with antipsychotics, mood stabilizers, isoniazid (a drug for tuberculosis [TB]), glucocorticoids/mineralocorticoids, psychostimulant appetite suppressants, or centrally active antihypertensive drugs

• Treatment with hormones, antidepressants, or opioids within 6 months prior to study entry

• Treatment with sedative hypnotic medications or over-the-counter sleeping aids within 1 month prior to study entry

• Diagnosis of depression

• Competitive exercise, or exercise exceeding 1 hour each day

• Regular smoking within 5 years prior to study entry

Related Conditions & MeSH terms

• Pain

Intervention

Procedure:
• Hypertonic saline
To elicit pain
• Isotonic saline
Non-painful control

Locations

Country	Name	City	State
United States	University of Michigan Medical Center	Ann Arbor	Michigan

Sponsors (2)

Lead Sponsor	Collaborator
University of Michigan	National Center for Complementary and Integrative Health (NCCIH)

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Placebo-induced activation of brain opioid neurotransmission		90 min