Vasopressin binds to microvessels from rat hippocampus

Abstract

Recent evidence suggests that vasopressin may influence the permeability of the endothelium of brain capillaries. We measured the binding of [ 125I]arginine-8-vasopressin ([ 125I]AVP) to microvessels isolated from different regions of the rat brain. The study revealed saturable and specific binding of [ 125I]AVP to microvessels isolated from hippocampus. Scatchard analysis confirmed a single class of high affinity sites with an equilibrium dissociation constant, K d , of 3.2 nM and an apparent maximal binding capacity of 205 fmol/mg protein. No binding was observed to microvessels from neocortex and striatum.