A comparison was made of the permeabilities of different neurotrophic factors at the blood-
brain barrier (BBB) and blood-nerve barrier (BNB) in normal adult rats by quantifying the
permeability coefficient-surface area (PS) product after correction for the residual plasma
volume (Vp) occupied by the protein in the capillary bed of the nerve endoneurium or
different brain regions. The iv bolus injection technique was used in the cannulated brachial
vein and artery using the same protein radioiodinated with a second isotope of iodine (125I …