Restoration of Retinal Vascular Responses in Diabetic Patients

What is the Study about?

This study will examine if aminoguanidine, an experimental test agent, improves blood flow in the retina and contrast sensitivity in the eyes of people with diabetes.
Diabetic retinopathy is the leading cause of blindness in the developed world. The causes of the disease are poorly understood. One of the earliest changes that occur in the eyes of diabetic patients is a decrease in how well light increases blood flow in the inner lining of the eye called the retina. We recently found that aminoguanidine prevents this decrease from happening in experimental animals and now would like to determine if aminoguanidine can prevent this change in blood flow in people with diabetes.

Eligibility to participate

You may be eligible to participate in this Study if you:

  • Are under 55 years of age
  • Have Type 1 diabetes for 5 -20 years
  • Have no diabetic retinopathy
  • Have no history of eye complications

This study is also accepting healthy participants.
This study is currently recruiting participants.

What is involved in the Study?

Participants with diabetes and healthy participants will visit the University of Minnesota a total of 3 times:

  • 1st visit (screening visit) – You will have a general exam including a medical history, and a blood sample will be taken.
  • 2nd visit – A dilated eye exam will be performed and measurement of retinal blood vessel dilation will be taken before and after aminoguanidine ingestion. This visit will take approximately 5-6 hours.
  • 3rd visit – A contrast sensitivity test will be done before and after aminoguanidine ingestion. This visit will take approximately 3-4 hours.

Some healthy participants will be asked to complete a standardization protocol which consists of 1 visit for approximately 3-5 hours. During this visit a general exam with a medical history will be taken, contrast sensitivity measured, a dilated eye exam performed, and measurement of retinal blood vessel dilation performed.


Principal Investigator

Elizabeth Seaquist, MD

For More Information

Abdisa Taddese
(612) 624-1469