Shunting in chronic hydrocephalus induces VEGFR-2 and blood vessel density changes in the caudate nucleus

Abstract

Background Chronic hydrocephalus (CH), which is characterized by increased cerebrospinal (CSF) fluid volume with or without increased intracranial pressure (ICP), is often associated with decreased cerebral blood flow and oxygen delivery. While CSF shunting can improve neurological symptoms, the cause of these symptoms in hydrocephalus and the mechanism of shunt reversal remain unclear. We have previously observed a decreased cerebral blood flow in CH which was associated with a stimulation of Vascular Endothelial Growth Factor Receptor- 2 (VEGFR-2) expression and changes in vascular density. In this study we investigated the effect of shunting on neuronal and glial VEGFR-2 expression and blood vessel densities (BVd) in the caudate nucleus. Materials and methods Fourteen (n=14) young adult canines were divided into three groups: CH-Shunted (CH-S, shunted at 12 weeks, n=4); CH-Untreated hydrocephalic (CHU, 12-16 weeks, n=5); and Surgical Controls (SC, 12-16 weeks, n=5). The experimental model of CH used was previously developed and investigated in our lab. The density of blood vessels and VEGFR-2 positive neurons and glia was estimated using stereological counting methods and expressed as a percent (%) of total cells. Results