Clinical Research Directory

Inclusion Criteria: * Female * Ages 30 - 50 years * Self-reported menses occurrence within past 12 months * Diagnosis of ER+/HER2- breast cancer * Willing and able to comply with study procedures * Willing and able to provide consent Exclusion Criteria: * Untreated thyroid disorder * Untreated diabetes * BMI \>30 * Current treatment with metformin * Diagnosed neuromuscular disease * Diagnosed neurovascular disease * Prior history of cognitive impairment * Prior history of chemotherapy treatment * HIV, Hepatitis B or Hepatitis C * Systolic blood pressure \<90 or \>170, diastolic blood pressure \<50 or \>110 after repeated evaluation with proper cuff. This range is the acceptable range stated in the prescribing information for sildenafil (\>90/50 and \<170/110) * Use of alpha blockers in the past 2 weeks * Use of PDE5 inhibitors in the past 2 weeks * Use of nitrates * Subjects with MRI incompatible devices * Subjects with severe claustrophobia * Any medical condition that, in the opinion of the investigator, would place the subject at increased risk for participation