Free radicals in retinal and choroidal blood flow autoregulation in the piglet : interaction with prostaglandins

Purpose. To study the role of free radicals in autoregulation of retinal blood flow (RBF) and choroidal blood flow (ChBF) and the contribution of the cyclooxygenase pathway in free radical formation during blood pressure changes in 1- to 3-day-old pigs. Methods. Blood pressure was adjusted by inflating balloon-tipped catheters placed at the aortic isthmus and the aortic root to induce hypertension and hypotension, respectively. Blood flow was measured using the microsphere technique. Also, the effects of peroxides on retinal artery diameter were studied on eyecup preparations using time-frame photography processed by digital imaging