Effects of Indomethacin on Retinal and Choroidal Blood Flow in Healthy Volunteers
Status:
Completed
Trial end date:
2006-08-01
Target enrollment:
Participant gender:
Summary
Prostaglandins (PG) are known to alter regional ocular blood flow and exhibit vasoactive
properties in isolated ocular blood vessels. A variety of animal experiments indicate that
endogenous PGs play a role in the regulation of retinal (RBF) and choroidal (ChBF) blood
flow. There is also evidence that the prostaglandin pathway is involved in the activation of
NO production in humans, however, the mechanisms for interactions between PG and NO in ocular
vasculature are still unclear.
Animal studies suggest that retinal and choroidal blood flow decrease after administration of
indomethacin (a nonspecific cyclooxygenase inhibitor). More recently, it has been shown that
indomethacin injected intravenously decreased optic nerve oxygen tension and reduced the CO2
reactivity. This is probably the result of decreased blood flow through vasoconstriction of
vessels in the optic nerve. Systemic administration of indomethacin also diminishes cerebral,
renal and mesenteric blood flow by an unknown mechanism. However, no clinical trials exist so
far investigating the effects of indomethacin on ocular blood flow. Therefore, the aim of
this study is to investigate the effect of indomethacin on ocular blood flow in healthy
humans.