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CompletedNCT00001752Updated Mar 4, 2008

Vascular and Metabolic Effects of Hormone Therapy Combined With L-Arginine in Postmenopausal Women

A Phase 2 interventional study of L-arginine and Estrogen in Hypercholesterolemia and Postmenopause, sponsored by National Heart, Lung, and Blood Institute (NHLBI). Completed at 1 site in United States. Open to female participants, including healthy volunteers. Per ClinicalTrials.gov, last updated 2008-03-04.

Sponsored by National Heart, Lung, and Blood Institute (NHLBI) · Phase 2, Interventional, and Treatment

Phase
Phase 2
Study type
Interventional
Enrollment
30
Sex
Female
01

Study summary

Estrogen therapy has been associated with reduced risk of coronary heart disease events in observational studies of postmenopausal women. Although favorable effects of estrogen on lipoprotein cholesterol levels probably account for much of this benefit, direct vascular effects (vasomotor, hemostatic, anti-inflammatory) regulated by nitric oxide (NO) may also be of importance. We have recently shown that vasodilator effects of estrogen in the coronary circulation are due to enhanced bioactivity of NO released from the endothelium. Estrogen has been shown to stimulate synthesis and activity of the enzyme NO synthase with enhanced NO synthesis in endothelial cells in culture. Because L-arginine is the natural substrate for the enzyme NO synthase, we propose that the combination of L-arginine and estrogen might have additive vasomotor, hemostatic and anti-inflammatory effects in hypercholesterolemic postmenopausal women.

Read the detailed description

Estrogen therapy has been associated with reduced risk of coronary heart disease events in observational studies of postmenopausal women. Although favorable effects of estrogen on lipoprotein cholesterol levels probably account for much of this benefit, direct vascular effects (vasomotor, hemostatic, anti-inflammatory) regulated by nitric oxide (NO) may also be of importance. We have recently shown that vasodilator effects of estrogen in the coronary circulation are due to enhanced bioactivity of NO released from the endothelium. Estrogen has been shown to stimulate synthesis and activity of the enzyme NO synthase with enhanced NO synthesis in endothelial cells in culture. Because L-arginine is the natural substrate for the enzyme NO synthase, we propose that the combination of L-arginine and estrogen might have additive vasomotor, hemostatic and anti-inflammatory effects in hypercholesterolemic postmenopausal women.

02

Conditions studied

  • Hypercholesterolemia
  • Postmenopause

Keywords

  • Adhesion Molecules
  • Endothelial Function
  • Inflammation
  • Lipoproteins
  • Nitric Oxide
  • Hormone Therapy
  • Postmenopausal Women
03

In context

Hypercholesterolemia

1,238 studies on the registry are indexed under Hypercholesterolemia; 109 are open to participants now.

This study's enrollment of 30 is below the median of 99 across 991 interventional studies indexed under Hypercholesterolemia.

Browse Hypercholesterolemia studies →

Lead sponsor

National Heart, Lung, and Blood Institute (NHLBI) is the lead sponsor of 1,117 studies on the registry; 71 are open to participants now.

Of its 57 completed or terminated interventional studies of FDA-regulated products, 49 (86%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
Child (0–17), Adult (18–64), Older adult (65+)
Sexes eligible
Female
Accepts healthy volunteers
Yes

Eligibility criteria

All volunteer subjects will be assessed for study participation, including a cardiovascular physical examination and resting electrocardiogram. Fasting blood will be taken for SMAC, CBC, thyroid battery, lipid levels, estradiol and FSH levels under screening protocol 94-H-0045. A urine pregnancy test will be performed in women with a uterus and cessation of menses less than 6 months. Aspirin and non-steroidal anti-inflammatory drugs and steroidal drugs (oral, ointment, drops or inhalation) will be stopped 10 days prior to starting the study and discontinued throughout the study.

Thirty hypercholesterolemic (LDL greater than 130 mg/dL) postmenopausal women who have not taken estrogenic hormone, antioxidant vitamins (A, C, E), or lipid-lowering therapy in the preceding 2 months will be selected to take part in this double-blind, cross-over study.

No subjects with plasma estradiol level greater than 50 pg/ml and FSH less than 50 pg/ml.

No subjects with blood pressure greater than 160/100 mm/Hg (off medication).

No subjects smoking cigarettes within 6 months.

No pregnant subjects.

No subjects with a history of deep venous thrombosis/pulmonary embolus.

No subjects with important chronic medical conditions (cancer, coronary artery disease, diabetes mellitus, COPD, renal disease) other than hypothyroidism if the subject is euthyroid on thyroid replacement.

No subjects who refuse to follow nitrate-restricted diet for 3 days prior to each study.

05

Study design

Phase
Phase 2
Primary purpose
Treatment
Enrollment
30 participants

Interventions

  • DrugL-arginine
  • DrugEstrogen
06

Study locations

1 site
  • National Heart, Lung and Blood Institute (NHLBI)
    Bethesda, Maryland 20892, United States
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References and documents

Publications

  • Guetta V, Quyyumi AA, Prasad A, Panza JA, Waclawiw M, Cannon RO 3rd. The role of nitric oxide in coronary vascular effects of estrogen in postmenopausal women. Circulation. 1997 Nov 4;96(9):2795-801. doi: 10.1161/01.cir.96.9.2795. PubMed 9386140 ↗
  • Hayashi T, Fukuto JM, Ignarro LJ, Chaudhuri G. Basal release of nitric oxide from aortic rings is greater in female rabbits than in male rabbits: implications for atherosclerosis. Proc Natl Acad Sci U S A. 1992 Dec 1;89(23):11259-63. doi: 10.1073/pnas.89.23.11259. PubMed 1454805 ↗
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Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Mar 4, 2008, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT00001752
Lead sponsor
National Heart, Lung, and Blood Institute (NHLBI)
First posted
Dec 10, 2002
Start date
Sep 1998
Completion
Jul 2000
Last update
Mar 4, 2008
View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in Aug 1999. You cannot join it, but the record below documents what was studied.

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