Retinal blood flow in diabetes.
OBJECTIVE
This is a review of work focused on characterizing retinal blood flow in diabetes. The review describes results on validation of the methodology for retinal blood flow measurements, the mechanisms of action of various factors that contribute to abnormalities in retinal blood flow in diabetic rodent models, and the translation of these results to clinical studies demonstrating the effectiveness of different therapeutic agents in normalizing retinal blood flow abnormalities in patients with diabetes.


METHODS
Retinal blood flow measurements were performed using video fluorescein angiography, a methodology that is based on the measurement of fluorescein dye circulation times through the retinal circulation.


RESULTS
The results of a number of experiments are summarized, detailing the effects of hyperglycemia and the roles of factors such as protein kinase C activation, endothelin-1 and endothelin-3, angiotensin-II, and nitric oxide in the development of retinal blood flow abnormalities in diabetes.


CONCLUSIONS
The measurement of retinal blood flow both in animals and in clinical trials using the same retinal blood flow measurement methodology can provide a valuable method of quantitation allowing characterization of physiological effects and their association with metabolic alterations in diabetes and their effects on the development and incidence of microvascular complications.
Clermont
Allen C
AC
Joslin Diabetes Center and Harvard Medical School, Eye Research Section, Boston, Massachusetts 12215, USA.
Bursell
Sven-Erik
SE
D000792:Angiography; D000818:Animals; D003930:Diabetic Retinopathy / Q000503:physiopathology*; D006801:Humans; D012039:Regional Blood Flow / Q000502:physiology*; D012171:Retinal Vessels / Q000502:physiology*