Sex Hormone and Vascular Function in Women With CKD

Inclusion Criteria: 1. Pre- (18-44 y) and post-menopausal (55-75 y) women 2. Individuals with CKD including stage 3-4 (eGFR 15-59 ml/min/1.73m2) determined by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation AND/OR urinary albumin-creatinine ratio (UACR) ≥ 30. 3. Controls must be healthy (free from hypertension, kidney disease, cardiovascular disease, diabetes, and other chronic disease as assessed by self-report, medical history, and screening labs). Premenopausal healthy women must have a regular menstrual cycle (25-35 d). Exclusion Criteria: 1. Perimenopausal (45-54 y) women 2. Pregnancy, lactation, or less than one year post-partum 3. Use of hormonal birth control methods, hormone replacement therapy, or a levonorgestrel intrauterine device (IUD) insertion for a duration less than 6 months 4. Advanced CKD requiring dialysis 5. History of kidney transplant 6. Use of immunosuppressant medications (unless taking a stable dosage for a quiescent disease in CKD group) 7. Antioxidant and/or omega-3 fatty acid use within the 2 weeks prior to testing 8. Current tobacco or nicotine use or history of use in the last 12 months 9. Marijuana use within 2 weeks prior to testing 10. Uncontrolled hypertension in CKD group (BP \>140/90 mmHg) 11. Atrial fibrillation 12. Active infection or antibiotic therapy 13. Hospitalization in the last month