Sexually Dimorphic Effects of GHRH in Adult Growth Hormone Testing

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00324064
Recruitment Status : Completed
First Posted : May 10, 2006
Last Update Posted : March 5, 2010
Information provided by:
Children's Mercy Hospital Kansas City

Brief Summary:

Specific Aim 1 Healthy male and female subjects and growth hormone (GH) deficient subjects display sexually dimorphic GH responses to GHRH administration

Specific Aim 2 GH responses to GHRH in both healthy controls and in GH deficient patients correlate with expression and activity of the stimulatory G proteins, G alpha q and G alpha S. G protein levels correlate with gonadal steroid levels.

Specific Aim 3 Sexually dimorphic GH responses to GHRH are enhanced in Tanner Stage V compared to Tanner Stage 1 individuals

Condition or disease Intervention/treatment Phase
Growth Hormone Deficiency Procedure: GHRH/arginine stimulation testing Not Applicable

Detailed Description:

Growth hormone deficiency affects disproportionately more males than females. Although ascertainment bias plays a role in this sexual dimorphism, no plausible mechanism to fully explain this difference has been proposed.

This investigator initiated study will provide currently unavailable data on sexual/age differences in response to GH stimulation testing. Data obtained from the study may provide a basis for developing appropriate normal ranges for adult GH testing, may provide a plausible mechanism for the enhanced hormone responsiveness observed in females, and may provide data on when the sexual differences to GH stimulation may develop.

The objectives of this study are to:

  1. Confirm the sexual dimorphism in growth hormone responses for adult growth hormone testing in healthy male and female subjects
  2. Correlate peak Growth Hormone Releasing Hormone (GHRH)/arginine induced growth hormone responses with G protein levels in healthy subjects and in patients with a history of childhood GH deficiency
  3. Determine whether sexual dimorphism is acquired during puberty

Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 90 participants
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Diagnostic
Official Title: Sexually Dimorphic Effects of GHRH in Adult Growth Hormone Testing
Study Start Date : July 2007
Actual Primary Completion Date : July 2009
Actual Study Completion Date : July 2009

Intervention Details:
    Procedure: GHRH/arginine stimulation testing
    GHRH(Geref) 1mcg/kg IVP followed by Arginine 10% solution 0.5mg/kg (maximum of 30 Gm) infused over 30 minutes. Labs drawn 6 times over 2 hours.

Primary Outcome Measures :
  1. Serum GH levels in response to GHRH/arginine stimulation [ Time Frame: End of study ]

Secondary Outcome Measures :
  1. mRNA and protein levels of G alpha q and G alpha S stimulatory proteins [ Time Frame: end of study ]
  2. Serum gonadal steroid levels in the three subject groups [ Time Frame: end of study ]

Information from the National Library of Medicine

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Ages Eligible for Study:   5 Years to 40 Years   (Child, Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

Healthy subjects

  • Males and females, Tanner stage V aged 15-40 years of age with no known endocrine problems
  • Males and females, Tanner stage I, aged 5-8 years with no known endocrine problems

GH subjects - Males and females, Tanner stage V, aged 15-21 years with a history of childhood growth hormone deficiency

Exclusion Criteria:

Healthy subjects

  • History of GH deficiency or treatment or other known endocrine disorder
  • Current height or adult height <5th %
  • Female subjects using hormonal methods of birth control
  • Female subjects with irregular menstrual cycles

GH subjects

- Subjects with GH deficiency who have not discontinued GH treatment for at least 2 months

Information from the National Library of Medicine

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 identifier (NCT number): NCT00324064

United States, Missouri
Children's Mercy Hospital
Kansas City, Missouri, United States, 64108
Sponsors and Collaborators
Children's Mercy Hospital Kansas City
Principal Investigator: Jill Jacobson, MD Children's Mercy Hospital

Responsible Party: Mark Clements, Children's Mercy Hospitals and Clinics Identifier: NCT00324064     History of Changes
Other Study ID Numbers: 06 03-053
First Posted: May 10, 2006    Key Record Dates
Last Update Posted: March 5, 2010
Last Verified: March 2010

Keywords provided by Children's Mercy Hospital Kansas City:
Growth hormone deficiency

Additional relevant MeSH terms:
Endocrine System Diseases
Dwarfism, Pituitary
Bone Diseases, Developmental
Bone Diseases
Musculoskeletal Diseases
Bone Diseases, Endocrine
Pituitary Diseases
Hypothalamic Diseases
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases
Hormones, Hormone Substitutes, and Hormone Antagonists
Physiological Effects of Drugs