Hypoglycemia | Evaluation of the Effect of Hypoglycemia With PET and a Norepinephrine Transporter Ligand

Hypoglycemia research study

What is the primary objective of this study?

The aim of this study is to use Positron Emission Tomography (PET) imaging to measure changes in norepinephrine transporter (NET) concentrations in the brain and periphery of healthy individuals during hypoglycemia. We hypothesize that during hypoglycemia, NE levels will increase within the brain, especially the hypothalamus, and this likely contributes to activation of glucose counterregulatory responses. We further hypothesize that during hypoglycemia, NET concentrations in key glucoregulatory regions will change in order to sustain or prolong sympathetic nervous system activation of counterregulatory responses.

Who is eligible to participate?

Inclusion Criteria: 1. Males or females between 18 and 55 years of age 2. Who are able to give voluntary written informed consent 3. Able to tolerate PET and MR imaging 4. Have clinical laboratory test results within normal reference range for the population or investigator site, or results with acceptable deviations that are judged to be not clinically significant by the investigator. 5. Have no current uncontrolled medical condition such as neurological, cardiovascular, endocrine, renal, liver, or thyroid pathology 6. Have no history of a neurological or psychiatric disorder 7. No history of previous allergic reactions to drugs 8. Do not suffer from claustrophobia or any MRI contradictions Exclusion Criteria: 1. History of liver disease 2. Pregnancy/breast feeding (as documented by pregnancy testing at screening and on days of the imaging studies). 3. Anemia (Hct <37 in women and < 40 in men) 4. Presence of acute or unstable medical or neurological illness. Subjects will be excluded from the study if they present with any history of serious medical or neurological illness or if they show signs of a major medical or neurological illness on examination or lab testing including history of seizures, head injury, brain tumor, heart, liver or kidney disease, eating disorder, diabetes. 5. Drug abuse (except nicotine)(Nicotine dependence will be permitted in all groups but controlled for in the analysis). 6. Use of antidepressants. 7. Clotting disorders or recent anticoagulant therapy. 8. MRI-incompatible implants and other contraindications for MRI, such as pace-maker, artificial joints, non-removable body piercings, tattoos larger than 1 cm in diameter, claustrophobia, etc 9. Clinically significant pulmonary, renal, cardiac or hepatic impairment or cancer, have clinically significant infectious disease, including AIDS or HIV infection, or previous positive test for hepatitis B, hepatitis C, HIV-1, or HIV-2; subjects will be asked about this. No testing will be performed. 10. Have received a diagnostic or therapeutic radiopharmaceutical within 7 days prior to participation in this study. 11. Blood donation during the 8-week period preceding the PET scan. 12. Participation in other research studies involving ionizing radiation within one year of the PET scans that would cause the subject to exceed the yearly dose limits for normal volunteers. 13. Unable to fast overnight prior to the PET scan.

Which medical condition, disease, disorder, syndrome, illness, or injury is researched?


Study Interventions

Interventions can include giving participants drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available or noninvasive approaches such as surveys, education, and interviews.

Other:Norepinephrine Transporter (NET) ligandNorepinephrine Transporter (NET) ligand for iv administration during Positron Emission Tomography scan to measure changes in brain NET concentration based on insulin levels.

Study Arms

Research studies and clinical trials typically have two or more research arms. An arm is a group of people who receive the same treatment in the study.

Healthy, lean subjectsVolunteers without anemia (hematocrit), diabetes (A1c), use of illicit drugs and antidepressants, or any other major health issues.

Study Status


Start Date: June 2011

Completed Date: June 2017


Type: Observational


Primary Outcome: norepinephrine transporter (NET) ligand concentrations at Baseline

Secondary Outcome:

Study sponsors, principal investigator, and references

Principal Investigator: Renata Belfort De Aguiar, MD

Lead Sponsor: Yale University


More information:

Discuss Hypoglycaemia