Hot Flashes, Menopause, Vasomotor System; Labile
Conditions
Keywords
Neurovascular function, Autonomic function, Microvascular Function
Brief summary
Women who experience hot flashes are at greater risk for hypertension and other cardiovascular disease. Neurovascular control mechanisms are likely to play an important role in this relationship. As such, these studies are designed to provide a major step forward in understanding the link between hot flashes and neurovascular dysfunction and, by extension, cardiovascular disease in women.
Interventions
OTHERSympathoexcitatory stressors
Muscle sympathetic nerve activity will be measured continuously at baseline and in response to sympathoexcitatory stressors, including a Valsalva maneuver, isometric handgrip exercise, a cold pressor test, and stepped hypercapnia.
DRUGSodium Nitroprusside
Sodium nitroprusside, used to test endothelium-independent vasodilation, will be infused through a brachial artery catheter at 0.25, 0.5, 1.0 and 2.0 ug/100ml tissue/min.
DRUGAcetylcholine
Acetylcholine, used to test endothelium-dependent vasodilation, will be infused through a brachial artery catheter at 1.0, 2.0, 4.0, and 8.0 μg/100ml tissue/min
DRUGTerbutaline
Terbutaline, a β2-Adrenergic selective agonist, will be infused through a brachial artery catheter at 0.1, 0.5, 1.0, and 2.0 μg/100ml tissue/min.
DRUGNorepinephrine
Norepinephrine, an α-adrenergic vasoconstricting agent, will be infused through a brachial artery catheter at 1.0, 2.0, 4.0, and 8.0 ng/100ml tissue/min
Sponsors
Mayo Clinic
National Institutes of Health (NIH)
National Heart, Lung, and Blood Institute (NHLBI)
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
FEMALE
Age
40 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
* Non-smokers. * Non-obese. * Have at least one ovary. * Free from cardiovascular disease. * Not taking medications influencing cardiovascular function.
Exclusion criteria
\- None.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Compare microvascular function in women with low and high frequency hot flashes | Continuous measurement of vascular conductance during infusion of each drug- 3min at baseline and at each drug dose (~60min total of continuous forearm vascular conductance measurements) | Change in forearm vascular conductance with intra-arterial drug infusions. Vascular conductance is an index of vascular tone and is assessed using a technique called venous occlusion plethysmography |
| Compare sympathetic function in women with low and high frequency hot flashes | Continuous measurement of muscle sympathetic nerve activity at rest and in response to stressors (~75min of continuous data collection once a sympathetic nerve signal is found) | Muscle Sympathetic Nerve Activity will be directly using a technique called microneurography. |
Countries
United States
Contacts
CONTACTPamela A Engrav
CONTACTNancy J Meyer
PRINCIPAL_INVESTIGATORSarah Baker, PhD
Mayo Clinic
Outcome results
None listed