Comparison of Intranasal Oxytocin Effects Using Co-administration With a Vasoconstrictor

Study Overview
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Brief Summary
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This study aims to dissociate direct from indirectly mediated effects of intranasal oxytocin administration by using treatment with or without prior intranasal administration of a vasoconstrictor to reduce peripheral increases in peptide concentrations. Primary outcomes of the randomized placebo-controlled double-blind experiment are blood oxytocin concentration and oxytocin-associated responses in central and peripheral systems. Intranasal application of the neuropeptide oxytocin has been reported to produce a number of neural, physiological and behavior effects which may be of potential therapeutic relevance, but it is unclear the extent to which they are mediated directly via the peptide entering the brain or indirectly as a result of increased peripheral concentrations. In the current placebo-controlled, double blind experiment on healthy adult male subjects the investigators will measure the effects of a single dose of intranasal oxytocin (24IU) on brain activity (using electroencephaolography - EEG) as well as on cardiac (heart-rate and heart-rate variablility) and gastric (electrogastrogram - EGG) activity and physiological arousal (skin conductance response - SCR). The pattern of functional effects observed will be compared with subjects receiving intranasal pretreatment with a vasoconstrictor prior to oxytocin in order to reduce the amount of oxytocin entering the peripheral circulation. The investigators hypothesize that prior administration of the vasoconstrictor will greatly reduce blood oxytocin concentrations following intranasal oxytocin treatment. Where neural/physiological effects are also affected, this will indicate an indirectly mediated action of intranasally administered oxytocin whereas if they are not this will indicate a directly mediated action.

Official Title
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Comparison of Direct and Indirect Effects of Intranasal Oxytocin Using Co-administration With a Vasoconstrictor

Conditions
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Healthy

Intervention / Treatment
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* Drug: vasoconstrictor and oxytocin treatment
* Drug: vasoconstrictor's placebo and oxytocin treatment
* Drug: vasoconstrictor and oxytocin's placebo treatment


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy subjects without past or current psychiatric or neurological disorders Exclusion Criteria: history of head injury medical or psychiatric illness.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 30 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: vasoconstrictor + intranasal oxytocin group<br>subjects receive the vasoconstrictor followed by oxytocin | Drug: vasoconstrictor and oxytocin treatment<br>* intransal administration of vasoconstrictor and oxytocin<br>|
| Active Comparator: vasoconstrictor's placebo + intranasal oxytocin group<br>subjects receive the vasoconstrictor's placebo followed by oxytocin | Drug: vasoconstrictor's placebo and oxytocin treatment<br>* intransal administration of vasoconstrictor's placebo and oxytocin<br>|
| Placebo Comparator: vasoconstrictor + intranasal oxytocin placebo group<br>subjects receive the vasoconstrictor followed by intranasal oxytocin's placebo | Drug: vasoconstrictor and oxytocin's placebo treatment<br>* intransal administration of vasoconstrictor and oxytocin's placebo<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| blood oxytocin concentration | blood oxytocin concentration changes following vasoconstrictor/placebo and oxytocin/placebo treament | 2 hours | 
| resting EEG time-frequency | resting EEG time-frequency changes following vasoconstrictor/placebo and oxytocin/placebo treament | 2 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| heartrate | heartrate (and heartrate variability) changes following vasoconstrictor/placebo and oxytocin/placebo treament | 2 hours | 
| skin conductance | skin conductance level (measured by skin conductance response) changes following vasoconstrictor/placebo and oxytocin/placebo treament | 2 hours | 
| gastrointestinal activity | gastrointestinal activity (measured by electrogastrogram) changes following vasoconstrictor/placebo and oxytocin/placebo treament | 2 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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EEG, vasoconstrictor, oxytocin, peripheral nervous system response