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NCT Number: NCT03255408

Cerebral Blood Flow and Ventilatory Responses During Sleep in Normoxia and Intermittent Hypoxia

A prospective double blind, placebo-controlled, randomized cross-over trial to evaluate the effect of lowering cerebral blood flow on the ventilatory chemoreflexes (acute hypoxic and hypercapnic ventilatory responses).

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Key information

Conditions

Obstructive Sleep Apnea of Adult Apnea Blood Pressure Brain Diseases Cardiovascular Diseases Central Nervous System Diseases Cerebrovascular Disorders Dyssomnias Endothelial Dysfunction Hypoxia Hypoxia, Brain Mental Disorders Nervous System Diseases Neurologic Manifestations Oxidative Stress Pathological Conditions, Signs and Symptoms Respiration Disorders Respiratory Tract Diseases Signs and Symptoms Signs and Symptoms, Respiratory Sleep Apnea Sleep Apnea Syndromes Sleep Disorder Sleep Disorders, Intrinsic Sleep Wake Disorders Stroke Vascular Diseases

Age range

18 year–45 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 1 / Phase 2

Primary location

University of Calgary

Calgary, Alberta, T2N 4N1, Canada

Location status: Recruiting

Location contact

Chair, Conjoint Ethics Board

CONTACT

[email protected]

About this study

The investigators will explore the relationship between changes in Cerebral Blood Flow (CBF) and ventilatory chemoreflexes i.e. Acute Ventilatory Response to Hypoxia (AHVR) and Acute Hypercapnic Ventilatory Response (HCVR) before, during and after sleep under normoxic conditions and sleep accompanied by isocapnic Intermittent Hypoxia (IH) among healthy human study participants.

A pharmacological intervention will be utilized to manipulate the CBF in a randomized order. The study participants will also be randomly assigned the order to sleep either under normoxia or IH exposure. The experiments will be separated from one another with an interval of sufficient drug and IH exposure washout period. The venous blood samples and urinary samples will be collected for the vascular biomarkers.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Healthy adults
  • 18 - 45 years of age
  • Living in Calgary for the past one year
  • Have no medical condition or should not be taking any blood pressure medications.
  • The participant should not be lactose intolerant

Exclusion criteria

  • Cerebrovascular, cardio-respiratory, renal and metabolic diseases
  • Bleeding disorders and upper gastrointestinal diseases e.g. peptic ulcer disease
  • Pregnancy, obese and sleep-disordered breathing
  • Drug allergies to non-steroidal anti-inflammatories
  • Currently smoking

Treatment and study plan

Drug Lowering Cerebral Blood Flow (CBF) and Normoxia Sleep

Drug

The study participants will take Cerebral Blood Flow (CBF) lowering drug and sleep under Normoxia Exposure

Other names: Cerebral Blood Flow changes and Normoxia Sleep

Drug Lowering CBF and Intermittent Hypoxia Sleep

Drug

The study participants will take Cerebral Blood Flow (CBF) lowering drug and sleep under Intermittent Hypoxia (IH) Exposure

Other names: CBF changes and Intermittent Hypoxia Sleep

Placebo and Normoxia Sleep

Drug

The study participants will take Placebo and sleep under Normoxia Exposure

Other names: Cerebral Blood Flow (CBF) with Placebo in Normoxia Sleep

Placebo and Intermittent Hypoxia Sleep

Drug

The study participants will take Placebo and sleep under Intermittent Hypoxia (IH) Exposure

Other names: CBF with Placebo in Intermittent Hypoxia Sleep

Primary outcomes

  1. Changes in cerebral blood flow and ventilatory chemoreflexes

    Time frame: ~18 months (from the starting time of recruiting study participants)

    The relationship between changes in cerebral blood flow (CBF) and ventilatory chemoreflexes (acute hypoxic and hypercapnic ventilatory responses) before and after sleeping under normoxia and intermittent hypoxia exposure among healthy human study participants.

  2. Cerebral blood flow responses and ventilatory chemoreflexes during sleep

    Time frame: ~18 months (from the starting time of recruiting study participants)

    The relationship between cerebral blood flow (CBF) changes and ventilatory chemoreflexes (acute hypoxic and hypercapnic ventilatory responses) during sleep under normoxia and intermittent hypoxia exposure among healthy human study participants.

Secondary outcomes

  1. Changes in reactive oxygen species and vascular biomarkers

    Time frame: ~24 months (from the starting time of recruiting study participants)

    The changes in vascular biomarkers such as nitric oxide, reactive oxygen species and exosome analysis or urinary prostaglandins before and after sleep under normoxia and intermittent hypoxia exposure with cerebral blood flow changes.

Sponsors and collaborators

Lead sponsor

University of Calgary

Other

Registry information

Official study title

Role of Cerebral Blood Flow on Ventilatory Stability During Sleep in Normoxia and Intermittent Hypoxia

Important dates

Study start
2023
Primary completion
2027
Study completion
2027
First posted
Aug 21, 2017
Registry last updated
May 1, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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