Participants will be recruited in three different age intervals: 18-45 years, 55-80 years and 80+ years. These participants will all undergo the same stimulation test with 0.1 mg LHRH, 0.2 mg TRH, and 0.25 mg ACTH (Synachten). The tests will be perfomed at the same time of day for all particpants (between 08:15 and 08:45) and participants will be fasting for the test. Blood samples will be taken just before and at 10, 20, 30, 45, 60, 90 and 120 minutes following the stimulation test. Serum from blood samples will be stored at -20 degrees until analysis.
The purpose of this study to age-related differences to the response of a combined pituitary stimulation test with TRH, LHRH and ACTH.