Growth Hormone Deficiency
Conditions
Keywords
Growth hormone deficiency
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
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
Interventions
PROCEDUREGHRH/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.
Sponsors
Children's Mercy Hospital Kansas City
Study design
Allocation
NON_RANDOMIZED
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
5 Years to 40 Years
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
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Serum GH levels in response to GHRH/arginine stimulation | End of study |
Secondary
| Measure | Time frame |
|---|---|
| mRNA and protein levels of G alpha q and G alpha S stimulatory proteins | end of study |
| Serum gonadal steroid levels in the three subject groups | end of study |
Countries
United States
Outcome results
None listed