Abdominal Obesity, Cardiovascular Inflammation, and Effects of Growth Hormone Releasing Hormone Analogue

Inclusion/Exclusion Criteria: Inclusion Criteria for Lean Controls: 1. Men and women age 18-55y 2. BMI \> 18.5 and \< 25 kg/m2 3. Waist circumference \< 102 cm in men and \<88cm in women Inclusion criteria for Abdominal Obesity: 1. Men and women age 18-55y 2. BMI ≥ 30kg/m2 3. Abdominal obesity as defined by waist circumference ≥ 102 cm in men and ≥ 88 cm in women 4. Relative GH deficiency as demonstrated by peak GH to arginine/GHRH stimulation test of \< 9mcg/L (for treatment portion only) 5. Negative age-appropriate screening for cancer performed by primary care physician (e.g., negative mammogram if F \> 50yo) (For treatment portion only) Exclusion criteria for all subjects: 1. Obesity due to known secondary causes 2. Use of weight-lowering drugs or previous weight loss surgery 3. Use of gonadal steroids, GH, GHRH, glucocorticoids, megesterol acetate, antidiabetic agents, or any other hormonal medication judged by the investigator to be inappropriate within the past 6 months. Use of physiologic testosterone replacement will be allowed. 4. Statin use 5. Known coronary artery disease or peripheral vascular disease, or any history of stroke or significant chest pain 6. Known auto-immune or inflammatory disease 7. Any surgery or significant injury (including fracture or other trauma) within the past 6 months 8. Hemoglobin \< 11g/dL, fasting glucose \> 126mg/dL, creatinine \<1.5mg/dL, or AST \> 2.5x upper limit of normal 9. FSH \> 20 IU/L (women only) 10. Positive urine pregnancy test, actively seeking pregnancy, or breastfeeding 11. Prior history of pituitary disease, pituitary surgery, or head irradiation, or any other condition known to affect pituitary function 12. Infectious illness in the past 3 months, or chronic infectious illness 13. Allergy to iodine containing contrast media 14. Active illicit drug use 15. For women of childbearing potential, failure to use an acceptable form of non-hormonal birth control 16. Active malignancy: For the treatment part of the study, all active malignancy will be excluded. For the observational part of the study (which involves no intervention) basal cell carcinoma and low grade cervical or anal intraepithelial neoplasms will be allowed. 17. History of colon cancer (treatment part only)