Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
Aging in men reduces the amount of luteinizing hormone (LH) and testosterone (Te) secreted in each burst. Stress-associated mechanisms introduced by acute illness and chronic disease decrease LH and Te secretion further. A major unresolved issue is whether the aging process heightens the negative effects of a stressor (whether physical or metabolic) upon LH and Te secretion. This study will assess LH and Te secretion in response to a physical stressor (maximal exercise) and a common metabolic stressor (hyperglycemia) as a function of age in healthy men ages 18-80 yr.
Not provided
Not provided
Not provided
Not provided
Not provided
| Label | Type | Description | Intervention Names |
|---|---|---|---|
| Hyperglycemia | Experimental | Hyperglycemia (rest controlled) will be induced by i.v. injection of 25 mL of dextrose 50% over 3 minutes with the subject supine. Includes blood draws and fasting requirements. |
|
| Saline | Placebo Comparator | Saline (rest controlled) will be induced by i.v. injection of 25 mL of saline over 3 minutes with the subject supine. Includes blood draws and fasting requirements. |
|
| Exercise | Experimental | Monitored exercise of 7-minute biking, 2-minute arm weights and a blood draw at the 10-minute time point will be repeated 3 times,which takes 30 minutes. Bilateral arm curls begin at 20 pounds and decrease by 5 pounds as needed to sustain 2 minutes of exercise at a rate of 1 complete curl every 2 seconds. Includes blood draws and fasting requirements. |
|
| Name | Type | Description | Arm Group Labels | Other Names |
|---|---|---|---|---|
| Hyperglycemia | Drug | Hyperglycemia (rest controlled) will be induced by i.v. injection of 25 mL of dextrose 50% over 3 minutes with the subject supine. |
|
| Measure | Description | Time Frame |
|---|---|---|
| Change in Testosterone concentration after 30 minutes of exercise | During the exercise visit subjects will perform an exercise test on a bike and lift weights with both arms for a total of 30 minutes. | 30 minutes after initiating exercise |
Not provided
Not provided
Inclusion Criteria:
Exclusion Criteria:
Not provided
Not provided
Not provided
Not provided
Not provided
| Name | Affiliation | Role |
|---|---|---|
| Johannes Veldhuis, MD | Mayo Clinic | Principal Investigator |
| Facility | Status | City | State | ZIP | Country | Contacts |
|---|---|---|---|---|---|---|
| Mayo Clinic in Rochester | Rochester | Minnesota | 55905 | United States |
Not provided
| ID | Term |
|---|---|
| D012965 | Sodium Chloride |
| D015444 | Exercise |
| D001800 | Blood Specimen Collection |
| ID | Term |
|---|---|
| D002712 | Chlorides |
| D006851 | Hydrochloric Acid |
| D017606 | Chlorine Compounds |
| D007287 | Inorganic Chemicals |
Not provided
Not provided
Not provided
Not provided
Not provided
Not provided
| Saline | Drug | Saline (rest controlled) will be induced by i.v. injection of 25 mL of saline over 3 minutes with the subject supine. |
|
| Exercise | Other | Monitored exercise of 7-minute biking, 2-minute arm weights and a blood draw at the 10-minute time point will be repeated 3 times,which takes 30 minutes. Bilateral arm curls begin at 20 pounds and decrease by 5 pounds as needed to sustain 2 minutes of exercise at a rate of 1 complete curl every 2 seconds. |
|
| Blood Draws | Procedure | Blood will be sampled every 10 min from 0700 to 1300 h. Each intervention will begin at 0800 h after 1 h of baseline sampling, and be completed by 0900 h. Intervention is followed by 4 additional h of sampling to capture recovery (total sampling 6 h). Ten-min samples are for Te, LH, ACTH, cortisol, and GH. Glucose will be checked every 30 min. At 07000 h an archival serum sample will be obtained for safety-monitoring purposes. |
|
| Fasting procedure | Other | Beginning at 1900 h on the evening prior to each study visit, subjects will remain fasting except for water, diet soda, and other non-caloric and non-caffeinated fluids, until 1300 h the next day. |
|
| D017670 |
| Sodium Compounds |
| D009043 | Motor Activity |
| D009068 | Movement |
| D009142 | Musculoskeletal Physiological Phenomena |
| D055687 | Musculoskeletal and Neural Physiological Phenomena |
| D013048 | Specimen Handling |
| D019411 | Clinical Laboratory Techniques |
| D019937 | Diagnostic Techniques and Procedures |
| D003933 | Diagnosis |
| D011677 | Punctures |
| D013514 | Surgical Procedures, Operative |
| D008919 | Investigative Techniques |