Currently, there is great interest in the assembly and function of cerebral endothelial, glial and neuronal cells that form the anatomical basis of the neurovascular unit (NVU) to maintain blood-brain barrier (BBB) and cerebral blood flow. Recent studies have provided considerable insight into the assembly of the components of the NVU. However, there is still paucity of data regarding the identification and expression pattern of these components in various pathologies of the central nervous system. Here, we provide a brief overview of the histological and imaging methods to study BBB disruption in various experimental settings especially the ischemia models associated with necrosis. Emphasis is on the immunohistochemistry of various protein markers of NVU. An understanding of the alterations in the expression pattern of these markers in various neurodegenerative disorders could lead to a better understanding of the conditions that cause BBB disruption as well as to the development of new restorative and protective treatments.