NVFU (NeuroVascular cerebrospinal Fluid Unit)

Abstract

We have come to the time to reconsider the bulk theory that have been hitherto upheld in explaining the cerebrospinal fluid as the third circulatory system next to the blood and lymph. There are possibilities that the cerebral capillaries serve as the site of generation and absorption of tissue and cerebrospinal fluids and as the drainage pathway for metabolic and waste products. If we assume that these functions of cerebrospinal fluid are disturbed when individuals enter pathological states or become aged, there are possibilities that the behaviors of the cerebrospinal fluid involve the neurovascular unit (NVU). Thus it is necessary to examine the correlation of these possibilities with the results of past experiments and clinical findings. If we are to believe that astrocytes, a component constituting NVU, are related to the water channel such as aquaporine, it becomes necessary to re-examine the cerebral blood circulation, which has hitherto been defined by the accepted theories and knowledge, in line with the added concept of cerebrovascular circulation. In the past, the studies on metabolism related to cerebrovascular circulation tended to lean heavily on blood circulation. For the future studies of neuroprotection, complex and comprehensive approaches, such as the concept of the NVFU (NeuroVascular cerebrospinal Fluid Unit) with spacial and functional expansion encompassing not only cerebrovascular but also cerebrospinal fluid circulations may be necessary.