The Effects of Aging and Estrogen on the Pituitary
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ClinicalTrials.gov Identifier: NCT00386022 |
Recruitment Status : Unknown
Verified April 2017 by Janet E. Hall, MD, Massachusetts General Hospital.
Recruitment status was: Active, not recruiting
First Posted : October 11, 2006
Results First Posted : April 13, 2017
Last Update Posted : April 13, 2017
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Condition or disease | Intervention/treatment | Phase |
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Healthy | Drug: GnRH Drug: NAL-GLU GnRH antagonist Drug: Estrogen patch | Phase 2 Phase 3 |
Although it is clear that loss of ovarian function plays a major role in the menopause in women, there is evidence from animal studies that primary age-related hypothalamic and pituitary changes may also contribute to reproductive aging. Complete cessation of ovarian function results in the loss of negative feedback of ovarian steroids and inhibin on the hypothalamic and pituitary components of the reproductive axis. An increase in serum levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) occurs in postmenopausal women with removal of negative ovarian feedback. However, levels of LH and FSH after menopause decline steadily as a function of age in most though not all studies.
The current study is designed to determine: 1) whether negative feedback on LH and FSH occurs at the pituitary; and 2) whether there is an effect of aging on estrogen negative feedback at the pituitary. Younger and older postmenopausal women underwent a baseline study and a second identical study after a month of low dose estrogen replacement. The study protocol consisted of the following: 1) administration of a GnRH antagonist (Nal-Glu at 150 mg/kg that blocks endogenous GnRH so that the dose and interval of pituitary exposure to GnRH are precisely controlled; 2) beginning 8 hours following GnRH antagonist administration (at a time when LH had reached its nadir following GnRH receptor blockade), administration of 4 graded doses of GnRH (25, 75, 250 and 750 ng/kg every 2 hours with 2 hours of blood draws following each dose). Blood was sampled every 30 min for 4 hours before antagonist administration, every 30 min for the following 7 hours and then every 10 min until the completion of the study.
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 19 participants |
Allocation: | Randomized |
Intervention Model: | Sequential Assignment |
Intervention Model Description: | The study will is considered sequential as participants were studied at baseline and after one month of low-dose estrogen. Randomization refers to randomization of the order of doses of GnRH between participants. |
Masking: | None (Open Label) |
Primary Purpose: | Other |
Official Title: | The Effect of Aging on the Isolated Pituitary Response to Gonadotropin Releasing Hormone at Baseline and With Low Dose Estrogen Administration |
Study Start Date : | January 2002 |
Actual Primary Completion Date : | January 2012 |
Estimated Study Completion Date : | January 2018 |

Arm | Intervention/treatment |
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Experimental: Young postmenopausal women
intervention: graded doses of GnRH following NAL-GLU GnRH antagonist administration with or without transdermal estrogen patch
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Drug: GnRH
GnRH doses of 25, 75, 250 and 750 ng/kg will be given IV every 4 hr at baseline and after transdermal estradiol
Other Names:
Drug: NAL-GLU GnRH antagonist A single subcutaneous injection of the NAL-GLU GnRH antagonist at a dose of 150 mcg/kg before and after transdermal estradiol
Other Name: GnRH antagonist Drug: Estrogen patch transdermal estrogen patches 0.05mg/day, changing the patch every 86 hr in second part of sequential study
Other Names:
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Experimental: Older postmenopausal women
intervention: graded doses of GnRH following NAL-GLU GnRH antagonist administration with or without transdermal estrogen patch
|
Drug: GnRH
GnRH doses of 25, 75, 250 and 750 ng/kg will be given IV every 4 hr at baseline and after transdermal estradiol
Other Names:
Drug: NAL-GLU GnRH antagonist A single subcutaneous injection of the NAL-GLU GnRH antagonist at a dose of 150 mcg/kg before and after transdermal estradiol
Other Name: GnRH antagonist Drug: Estrogen patch transdermal estrogen patches 0.05mg/day, changing the patch every 86 hr in second part of sequential study
Other Names:
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- Pituitary Response to GnRH [ Time Frame: Peak hormone level within 2 hours post GnRH doses ]Baseline LH and FSH responses to each of 4 GnRH doses - peak to nadir amplitude expressed as percent (%) change from nadir
- Effect of Estrogen on Pituitary Response to GnRH [ Time Frame: Peak hormone level within 2 hours post GnRH doses ]LH and FSH responses to each of 4 GnRH doses, expressed as change in amplitude [amp] from peak to nadir between plus estrogen and baseline conditions

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Ages Eligible for Study: | 45 Years to 80 Years (Adult, Older Adult) |
Sexes Eligible for Study: | Female |
Accepts Healthy Volunteers: | Yes |
Inclusion Criteria:
- 45-55 or 70-80 years old
- History of natural menopause defined by the absence of menses for at least 12 months (or history of surgical menopause defined as bilateral oophorectomy) and a FSH level >26 IU/L
- On no hormonal medication or herbal supplements and/or over the counter menopause therapy for a minimum of 2 months prior to study
- Normal thyroid stimulating hormone, prolactin, factor V Leiden, and complete blood count - Normal blood urea nitrogen and creatinine (< 2 times the upper limit of normal)
- basal metabolic index ≤ 30
- Non-smokers or smoke less than 10 cigarettes/day
Exclusion Criteria:
- Absolute contraindications to the use of physiologic replacement doses of estrogen, including a negative screening mammogram within the past 24 months
- History of coronary artery disease
- On medications thought to act centrally on the GnRH pulse generator
- Past history of hypersensitivity or allergy to narcotics, vancomycin, muscle relaxants, aspirin, and/or anaphylactic reaction(s) to other drugs
- Prior history of breast cancer and/or blood clots

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00386022
United States, Massachusetts | |
Massachusetts General Hospital | |
Boston, Massachusetts, United States, 02114 |
Principal Investigator: | Janet E Hall, M.D. | Massachusetts General Hospital |
Responsible Party: | Janet E. Hall, MD, Associate Physician, Massachusetts General Hospital |
ClinicalTrials.gov Identifier: | NCT00386022 |
Other Study ID Numbers: |
2000-P-002498 R01AG013241 ( U.S. NIH Grant/Contract ) |
First Posted: | October 11, 2006 Key Record Dates |
Results First Posted: | April 13, 2017 |
Last Update Posted: | April 13, 2017 |
Last Verified: | April 2017 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | Yes |
Plan Description: | Coded data with identifying information can be requested by contacting the PI. |
Gonadotropin-releasing hormone Estrogens postmenopausal women Pituitary hormones |
Pituitary Diseases Hypothalamic Diseases Brain Diseases Central Nervous System Diseases Nervous System Diseases Endocrine System Diseases Prolactin Release-Inhibiting Factors |
Estrogens LHRH, N-Ac-2-Nal(1)-4-Cl-Phe(2)-3-Pal(3)-Arg(5)-Glu(6)-AlaNH2(10)- Hormones Hormones, Hormone Substitutes, and Hormone Antagonists Physiological Effects of Drugs Hormone Antagonists |