Dopamine for Pulmonary Diffusion and Capillary Blood Volume during Exercise. However, since the Layman Condition List is "Health" which is very broad, it is difficult to specify a specific condition for this trial

Overseen By Wade W Michaelchuk, BSc

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: University of Alberta

Must not be taking: Dopaminergic drugs, Alcohol

Disqualifiers: Cardiac disease, Pulmonary disease, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 7

Duration: 2-3 weeks

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial explores how dopamine, a brain chemical, and the drug metoclopramide affect lung and heart function during exercise. The researchers aim to determine if these treatments can alter blood flow and lung function, particularly during physical activity. The trial seeks to establish whether these drugs could improve exercise tolerance, defined as the duration and intensity of exercise before fatigue sets in. It seeks active individuals who exercise more than twice a week and do not have heart or lung diseases. As an unphased trial, this study provides a unique opportunity to contribute to scientific understanding and potentially enhance exercise performance.

Will I have to stop taking my current medications?

You may need to stop taking certain medications, especially those that affect dopamine pathways, like some drugs for mood or brain function, alcohol, and certain painkillers.

Is there any evidence suggesting that this trial's treatments are likely to be safe?

A previous study found that dopamine did not significantly affect lung function or blood volume in the lungs during exercise for healthy participants. Some research suggests dopamine might aid breathing by reducing fluid buildup and improving muscle function, though these effects can vary.

Metoclopramide, often used for stomach issues, has some known side effects, including movement disorders, especially in children. While metoclopramide has been used safely for other conditions, individual reactions can differ.

Both dopamine and metoclopramide have been studied extensively, providing researchers with a good understanding of their safety. However, individual experiences may vary. ^{1 2 3 4 5}

Why are researchers excited about this trial's treatments?

Researchers are excited about this trial because it explores how dopamine and metoclopramide might improve lung function during exercise by affecting pulmonary diffusion and capillary blood volume. Dopamine is unique in that it is administered intravenously and may enhance blood flow and oxygen delivery to muscles during physical activity, offering a potential boost in exercise performance. On the other hand, metoclopramide is taken orally and could also influence lung function, but through different mechanisms related to its impact on the digestive system and possibly blood flow. By investigating these treatments, researchers hope to uncover new ways to optimize lung performance and overall exercise capacity.

What evidence suggests that this trial's treatments could be effective?

This trial will compare the effects of dopamine and metoclopramide on pulmonary diffusion and capillary blood volume during exercise. Research has shown that dopamine might influence blood flow through the lungs during exercise by acting on lung muscles, potentially aiding breathing during activity. However, other studies suggest dopamine might not significantly impact lung function in healthy individuals during exercise.

Metoclopramide, another treatment option in this trial, is commonly used to treat stomach issues like nausea, but no clear evidence indicates it affects lung function or exercise performance. Overall, findings are mixed regarding dopamine's potential benefits for lung function during exercise, and little information exists on metoclopramide's role in this area. ^{1 4 6 7 8}

Who Is on the Research Team?

Michael K Stickland, PhD

Principal Investigator

University of Alberta

Are You a Good Fit for This Trial?

This trial is for healthy, physically active individuals with a BMI under 30 who exercise more than twice a week. It's not suitable for those with known heart or lung diseases, high BMI over 30, on certain medications affecting dopamine pathways, or women who are pregnant.

Inclusion Criteria

I do not have any known heart or lung diseases.

Physically active (exercising >2 times per week)

BMI < 30kg/m2

Exclusion Criteria

I am not taking drugs that affect dopamine in my brain.

I am not pregnant.

I have a known heart or lung condition.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1 week

1 visit (in-person)

Baseline Testing

Pulmonary function and graded exercise testing to exhaustion to characterize aerobic fitness and lung function parameters

1 day

1 visit (in-person)

Treatment

Participants receive randomized treatments of dopamine, metoclopramide, or placebo with measurements at rest and during exercise

2-3 weeks

4 visits (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

1 week

1 visit (in-person)

What Are the Treatments Tested in This Trial?

Interventions

• Dopamine
• Metoclopramide

Trial Overview The study investigates how dopamine and blocking its receptors affect blood flow in the lungs and exercise tolerance. Participants will undergo different levels of exercise and receive either dopamine, metoclopramide (blocks dopamine-2 receptors), or placebos.

How Is the Trial Designed?

Group I: Placebos Experimental Treatment 4 Interventions

Dependent variables measured with orally ingested placebo pill and intravenous saline at rest, 60%, and 85% of VO2max

Group II: Metoclopramide Experimental Treatment 4 Interventions

Dependent variables measured with oral metoclopramide ingestion at rest, 60%, and 85% of VO2max

Group III: Dopamine Experimental Treatment 4 Interventions

Dependent variables measured with intravenous low dose dopamine infusion at rest, 60%, and 85% of VO2max

Who Is Running the Clinical Trial?

University of Alberta

Lead Sponsor

Trials

957

Recruited

437,000+

Natural Sciences and Engineering Research Council, Canada

Collaborator

Trials

63

Recruited

3,000+

Citations

1. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/31603268/

The effect of dopamine on pulmonary diffusing capacity ... Dopamine appears not to be important for regulating pulmonary diffusing capacity or pulmonary capillary blood volume during exercise in healthy participants.

2. clinicaltrial.be clinicaltrial.be/en/details/72403?per_page=20&only_recruiting=0&only_eligible=0&only_active=0

The Effect of Dopamine on Pulmonary Diffusion and Capilla... These results suggest that dopamine may modulate Vc during exercise via pulmonary smooth muscle regulation, subsequently affecting PVR, PAP, Q ...

3. journals.physiology.org journals.physiology.org/doi/10.1152/ajplung.00358.2024

Pulmonary capillary blood volume and diffusing membrane ... Collectively, these data indicate that acute increases in PAP during exercise potentiate the rise in DLCO via greater pulmonary capillary recruitment (i.e., DM) ...

4. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC5407706/

Assessment of Pulmonary Capillary Blood Volume ... Representative data showed that the DLCO, Vc, and Dm increased with exercise intensity. Echocardiographic data showed no IPAVA recruitment at ...

5. aging.networkofcare.org aging.networkofcare.org/sanmateo/CommunityResources/ClinicalTrials/Detail/NCT02965963?keyword=%22Health%22

The Effect of Dopamine on Pulmonary Diffusion and Capillary ... These results suggest that dopamine may modulate Vc during exercise via pulmonary smooth muscle regulation, subsequently affecting PVR, PAP, Q and exercise ...

6. sciencedirect.com sciencedirect.com/science/article/abs/pii/S1094553906001271

The effects of dopamine on the respiratory system DA may have beneficial effects on the respiratory system by decreasing oedema formation and improving respiratory muscle function, but can also have ...

7. journals.physiology.org journals.physiology.org/doi/abs/10.1152/jappl.1957.11.2.290

Relative Importance of Diffusion and Chemical Reaction ... Dm is about twice the value of Dl measured in subjects breathing air at sea level. Vc is about 75 ml in approximate agreement with the previously reported ...

8. ahajournals.org ahajournals.org/doi/10.1161/01.CIR.58.3.466

Comparative systemic and regional hemodynamic effects ... Dopamine (2--8 microgram/kg/min) increased the stroke volume and cardiac output at 4 microgram/kg/min. Dopamine at less than 4 microgram/kg/min provided little ...