Clinical trial NCT02928328: Assessment of Peripheral GABA Receptors for Local Pain Relief
Official title: Vurdering af Perifere GABAA-receptorer Med Henblik på Lokal Smertelindring
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Pain
Keywords: craniofacial pain
masticatory muscle
burning mouth syndrome
temporomandibular disorders
Lead sponsor: Aalborg University
Sponsor class: OTHER
First posted: 2016-10-10
Enrollment: 90
Sex: ALL
Minimum age (years): 20
Maximum age (years): 40
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: The effect of peripheral GABAA receptor activation on pain and sensitivity in healthy human subjects has never been investigated. However, as earlier studies suggest that activation of peripheral GABAA receptors is anti-nociceptive in rats, it is important to determine if these findings can be translated into human subjects to determine if peripheral GABAA receptors are a viable target for future analgesic drug development.

Detailed description: Subproject I This study will test if oral administration of GABA containing solutions will reduce the pain and sensitivity induced by application of capsaicin to the tongue of healthy human subjects. Thirty, pain-free men (n=15) and women (n=15) for the oral cavity study.

Subproject II This study will test the hypothesis that intramuscular injection of GABA alone will not be painful, but will reduce muscle pain sensitivity in healthy human subjects. Thirty, pain-free men (n=15) and women (n=15) will be recruited for the intramuscular GABA injection studies

Subproject III This study will test the hypothesis that intramuscular injection of GABA with glutamate will decrease the intensity of glutamate-evoked muscle pain in healthy human subjects. Thirty, pain-free men (n=15) and women (n=15) will be recruited for the intramuscular glutamate and GABA injection studies.

Eligibility criteria: Inclusion Criteria:

* Aged 20-40 years
* Free from ongoing or chronic pain
* Adequate conversational English

Exclusion Criteria:

* Pregnancy or intent to become pregnant, breast feeding
* Signs or symptoms of any serious systemic diseases
* Current malignancies
* High blood pressure
* Requirement for chronic administration of psychiatric, analgesic or other medications that might influence their response to pain
* Frequent recreational drug or alcohol use
* Previous neurologic, musculoskeletal or mental illnesses
* Lack of ability to cooperate

Primary outcomes:
measure: Pain Intensity Rating
timeFrame: continuously for 95 minutes
Secondary outcomes:
measure: Jaw Function Tests
timeFrame: every 5 min for 50 minutes
measure: Quantitative Sensory testing
timeFrame: every 10 min for 90 min
Other outcomes:
Locations:
city: Aalborg
country: Denmark
facility: Aalborg University
Study officials:
affiliation: Aalborg University
name: Brian E Cairns, PhD DrMed
role: PRINCIPAL_INVESTIGATOR
References:
citation: Zhang Y, Wang K, Arendt-Nielsen L, Cairns BE. gamma-Aminobutyric acid (GABA) oral rinse reduces capsaicin-induced burning mouth pain sensation: An experimental quantitative sensory testing study in healthy subjects. Eur J Pain. 2018 Feb;22(2):393-401. doi: 10.1002/ejp.1128. Epub 2017 Oct 11.