Studies on Regional Blood Flow of the Choroid Plexus

Regional blood flow of the choroid plexus was measured in dogs using the hydrogen clearance method and the data were compared with that obtained simultaneously in the cerebral cortex of the same animal. The choroid plexus was reached by means of unroofing the lateral ventricle in one hemisphere under an operating microscope. Measuring electrodes were platinum wire, 300μ in diameter, coated by epoxiresin. One millimeter of the tip of the electrode was bared of epoxi-resin and plated with platinum black. In order to measure choroidal blood flow, the tip of the electrode was bent rectangularly at the distance of 1 mm from the tip, and this bent tip of the electrode was twined by the exposed choroid plexus tissue. The other electrode of straight type was used for measurement of cortical blood flow on the opposite side. Regional blood flow of the choroid plexus of 24 normal dogs was 74.5 ± 13.5ml/100g/min in average which was higher than that of parietal cortex