PERMEABILITY OF BLOOD-TEAR BARRIER TO FLUORESCEIN AND ALBUMIN AFTER APPLICATION OF PLATELET-ACTIVATING-FACTOR TO THE EYE OF THE GUINEA-PIG

One of the inflammatory responses of the eye to local application of p latelet-activating factor (PAF) is oedema of the conjunctiva, caused b y extravasation of plasma. Aim of the study was to investigate if fluo rescein would leak from the blood into the tears together with plasma protein after application of PAF to the eye. Fluorescein was given int raperitoneally 30 min prior to application of 25 mu l of 0.1% solution of PAF. Thirty min after PAF the tear film was collected by washing t he surface of the eye with 25 mu l of phosphate buffered saline (PBS). Fluorescein in eye washings and in plasma was measured by fluorophoto metry and albumin by immunodiffusion. Both fluorescein and albumin app eared in a related fashion in tears, being absent in washings of place bo-treated control eyes. Extravasation of fluorescein can be used as a measure for plasma leakage in the conjunctiva with the advantage over the Evans Blue method that the former is a non-invasive method.