View clinical trials related to Pituitary Disease.
Filter by:The purpose of the study is to evaluate the effects of growth hormone (GH) replacement in men and women with a history of acromegaly and who are now growth hormone deficient. We will compare them to persons with a history of acromegaly who have normal GH levels. Acromegaly results when an area in the brain, called the pituitary, produces too much growth hormone. When an individual is cured of acromegaly, the growth hormone levels may be normal or low (that is GH deficiency). Growth hormone deficiency means the body no longer produces as much growth hormone because the pituitary/hypothalamic region was damaged by a tumor or by treatment received. We will study the effects of growth hormone replacement on the health of the heart and blood vessels of GH deficient persons by looking to see if this therapy: 1. has effects on cardiovascular risk markers (special blood tests which indicate how healthy your heart and arteries are) 2. affects the stiffness of the arteries 3. affects your heart rate and the capacity of your heart to respond to changes in body position 4. has different effects depending on whether you are taking estrogen / testosterone. We will assess these measures of health on one occasion in persons with cured acromegaly and normal GH levels and in persons with cured acromegaly who have GH deficiency and a contraindication to receiving GH. GH deficient individuals with no contraindication to receiving GH, will participate in the study for 12 months. Individuals with normal GH levels, or who are GH deficient and have a contraindication to receiving GH, will be asked to return for one more visit (without any interventions).
This study will determine the safety and activity of a new formulation of thyrotropin-releasing hormone (TRH), a drug used for diagnosing and evaluating patients with certain thyroid gland abnormalities. Normal thyroid gland function depends on proper chemical signaling between the thyroid gland, the hypothalamus (the part of the brain where TRH is made), and the pituitary (another part of the brain). The TRH test helps assess this interaction. Production of the only FDA-approved preparation of TRH was stopped in July 2002. As a result, to have a continuous source of TRH available for NIH clinical and research purposes, the NIH Clinical Center (CC) Pharmacy Department produced a pharmaceutical grade formulation of TRH for patient use. This study will test the CC formulation in healthy volunteers to show that its activity and side effects are similar to those of the previously available commercial test preparation. It will then be studied in CC patients for whom the diagnostic test is recommended. Healthy volunteers between 18 and 65 years of age and all patients requiring TRH evaluation of hypothalamic-pituitary-thyroid gland interaction may be eligible for this study. Patients include those with pituitary reserve, inconsistent thyroid function test, inappropriate TSH secretion, or pre- and post-operative evaluation of pituitary tumors. Normal volunteers will be screened with a medical history, physical examination, and blood tests. Women of child-bearing potential will be given a pregnancy test; pregnant and breast-feeding women may not participate. The TRH test procedure will be the same for healthy volunteers and patients. All participants fast from midnight before the morning of the test. In the morning, a catheter (flexible plastic tube) is inserted into an arm vein for easy injection of the TRH and collection of blood samples. Blood pressure is monitored before and during the test. A blood sample is drawn, and then TRH is given through the catheter over a 1-minute period. Another nine blood samples are collected over a 3-hour period from the time of the TRH injection for measuring levels of various hormones. A total of less than 4 tablespoons of blood is taken for the test.