Clinical trial NCT04105998: Effects of Intramuscular (IM) Oxytocin on Pupil Diameter and Heart Rate Variability (HRV)
Official title: Effects of Intramuscular Oxytocin on Pupil Diameter and Heart Rate Variability
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE4
Conditions: Chronic Pain Due to Injury
Keywords: Healthy Volunteer
Oxytocin
Pupillometry
Lead sponsor: Wake Forest University Health Sciences
Sponsor class: OTHER
First posted: 2019-09-26
Enrollment: 22
Sex: ALL
Minimum age (years): 18
Maximum age (years): 66
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: Double blinded crossover treatment with oxytocin and placebo (saline)
Primary purpose: BASIC_SCIENCE

Brief summary: The goal of this study is to test the effects of oxytocin on heart rate variability and pupil diameter, both of which have subtle effects on the activity rate of the autonomic nervous system.

Detailed description: This protocol focuses on two measures of autonomic control to quantify central actions of oxytocin. First, the study team proposes to examine the influence of oxytocin on heart rate variability with focus on its effect on high frequency variability, most commonly ascribed to parasympathetic nervous system activity acting to brake sympathetic tone. Intranasal oxytocin has been demonstrated to have a large effect size on this measure which can be repeated at frequent intervals. As a secondary assessment of parasympathetic activity, the study team will measure low frequency fluctuation in pupil diameter, termed hippus, which also reflects parasympathetic nervous system activity. This outcome measure can be assessed in 3 seconds using equipment currently being used under Institutional Review Board (IRB) approved protocols.

Eligibility criteria: Inclusion Criteria:

* Male or female \> 18 and \< 66 years of age,
* Body Mass Index (BMI) \<40
* Generally in good health as determined by the Principal Investigator based on prior medical history
* Normal blood pressure and resting heart rate without medication

Exclusion Criteria:

* Hypersensitivity, allergy, or significant reaction to any ingredient of Pitocin®
* Any disease, diagnosis, or condition (medical or surgical) that, in the opinion of the Principal Investigator, would place the subject at increased risk
* Women who are pregnant (positive result for serum pregnancy test at screening visit),
* Women who are currently nursing or lactating, women that have been pregnant within 2 years.
* Neuropathy, chronic pain, diabetes mellitus, or taking benzodiazepines or pain medications on a daily basis.
* Previous eye surgery, eye medications, cataracts

Primary outcomes:
measure: Fluctuation in Pupil Diameter (Hippus) -Pre Drug Administration
timeFrame: From 20 minutes before until study drug injection
measure: Fluctuation in Pupil Diameter (Hippus) -Post Drug Administration
timeFrame: For 90 minutes after study drug administration
measure: Fluctuation in Pupil Diameter (Hippus) -Post Drug Administration
timeFrame: For 120 minutes after study drug administration
measure: Heart Rate Variability in the High Frequency Range
timeFrame: From 20 minutes before until study drug injection
measure: Heart Rate Variability in the High Frequency Range
timeFrame: For 90 minutes after study drug administration
measure: Heart Rate Variability in the High Frequency Range
timeFrame: For 120 minutes after study drug administration
Secondary outcomes:
Other outcomes:
Locations:
city: Winston-Salem
country: United States
facility: Wake Forest Baptist Health
state: North Carolina
Study officials:
affiliation: Wake Forest University Health Sciences
name: James C Eisenach, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Norman GJ, Cacioppo JT, Morris JS, Malarkey WB, Berntson GG, Devries AC. Oxytocin increases autonomic cardiac control: moderation by loneliness. Biol Psychol. 2011 Mar;86(3):174-80. doi: 10.1016/j.biopsycho.2010.11.006. Epub 2010 Nov 30.
citation: Turnbull PR, Irani N, Lim N, Phillips JR. Origins of Pupillary Hippus in the Autonomic Nervous System. Invest Ophthalmol Vis Sci. 2017 Jan 1;58(1):197-203. doi: 10.1167/iovs.16-20785.