Mechanism(s) Underlying Hypotensive Response to ARB/NEP Inhibition - Aim 1

Inclusion Criteria: 1. Patients with essential hypertension defined as having 1. untreated, seated systolic blood pressure (SBP) of 130 mmHg or greater on three separate occasions, or 2. untreated, seated diastolic BP (DBP) of 80 or greater on three separate occasions, or 3. taken anti-hypertensive agent(s) for a minimum of six months. 2. For female subjects, the following conditions must be met: 1. postmenopausal status for at least one year, or 2. status post-surgical sterilization, or 3. if of childbearing potential, utilization of adequate birth control and willingness to undergo urine beta-human chorionic gonadotropin (hCG) testing prior to drug treatment and on every study day. Exclusion Criteria: 1. Presence of secondary form of hypertension 2. Symptomatic hypertension and/or SBP\>170 mmHg or DBP\>110 mmHg, relevant to the washout period 3. History of hypersensitivity or allergy to any of the study drugs, drugs of similar chemical classes, angiotensin-converting enzyme inhibitor (ACEi), ARBs, or NEPi, as well as known or suspected contraindications to the study drugs 4. History of angioedema 5. History of pancreatitis or known pancreatic lesions 6. History of significant cardiovascular disease (other than essential hypertension and left ventricular hypertrophy) 7. Symptomatic hypotension and/or a SBP\<100 mmHg at screening or \<95 mmHg during the study 8. Serum potassium \>5.2 mmol/L at screening or \>5.4 mmol/L during the study 9. Individuals using oral contraceptives and smokers in order to reduce the risk of thrombosis following arterial line placement 10. History of serious neurologic disease such as cerebral hemorrhage, stroke, seizure, or transient ischemic attack within six months 11. Presence of significant pulmonary disorders 12. Type 1 diabetes 13. Poorly controlled type 2 diabetes mellitus (T2DM), defined as a HgbA1c \>9% 14. Hematocrit \<35% 15. Impaired renal function \[estimated glomerular filtration rate (eGFR) of \<30 mL/min/1.73 m2\] as determined by the four-variable Modification of Diet in Renal Disease (MDRD) equation, where serum creatinine (Scr) is expressed in mg/dL and age in years: eGFR (mL/min/1.73m2)=175 • Scr-1.154 • age-0.203 • (1.212 if Black) • (0.742 if female) 16. Use of hormone-replacement therapy 17. Breast feeding and pregnancy 18. History or presence of immunological or hematological disorders 19. History of malignancy other than non-melanoma skin cancer 20. Diagnosis of asthma requiring use of inhaled beta agonist more than once a week 21. Clinically significant gastrointestinal impairment that could interfere with drug absorption 22. Impaired hepatic function \[aspartate amino transaminase (AST) and/or alanine amino transaminase (ALT) \>3.0 x upper limit of normal range\] 23. Any underlying or acute disease requiring regular medication which could possibly pose a threat to the subject or make implementation of the protocol or interpretation of the study results difficult, such as arthritis treated with non-steroidal anti-inflammatory drugs 24. Treatment with chronic systemic glucocorticoid therapy within the last year 25. Treatment with lithium salts 26. History of alcohol or drug abuse 27. Treatment with any investigational drug in the one month preceding the study 28. Mental conditions rendering the subject unable to understand the nature, scope, and possible consequences of the study 29. Inability to comply with the protocol, e.g., uncooperative attitude, inability to return for follow-up visits, and unlikelihood of completing the study