Racial Differences in Vagal Control of Glucose Homeostasis, Chronic Study

Inclusion Criteria * Female * African American or white (race will be self-defined, but only subjects who report both parents of the same race will be included) * 18-60 years old * BMI 30-45 Kg/m2 * Not pregnant or breastfeeding Exclusion Criteria * Pregnant or breastfeeding * Diabetes diagnosis (defined by the American Diabetes Association (ADA) criteria)38 * Cardiovascular disease such as myocardial infarction within 6 months prior to enrollment, presence of angina pectoris, significant arrhythmia, congestive heart failure (LV hypertrophy acceptable), deep vein thrombosis, pulmonary embolism, mitral valve stenosis, aortic stenosis, or hypertrophic cardiomyopathy. * Arrhythmia (first-, second-, and third-degree AV block) * Significant weight change \>5% in the past 3 months * Impaired hepatic function (AST and/or ALT \>1.5X upper limit of normal range) * Impaired renal function (eGFR \<60ml/min) * Users of strong inhibitors of CYP3A4 or CYP2D6 * Users of other acetylcholinesterase inhibitors such as pyridostigmine or bethanechol * History of alcohol or drug abuse * Mental conditions rendering the subject unable to understand the nature, scope, and possible consequences of the study * Inability to comply with the protocol, e.g., uncooperative attitude, inability to return for follow-up visits, and unlikelihood of completing the study * Steroid use within 6 weeks prior to study entry * 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 * Discretion of the investigator