1. Anatomical locations and organizations of the blood-brain and blood-cerebrospinal fluid barriers and the olfactory portal.
Anatomical locations and organizations of the blood-brain and blood-cerebrospinal fluid barriers and the olfactory portal. The skull and the meninges, which consist of the dura mater, arachnoid mater, and pia mater, protect the brain. The arachnoid mater and pia mater are connected by strands of connective tissue called arachnoid trabeculae, which course through the CSF-containing subarachnoid space. At the cellular level, the BBB and BCSFB maintain homeostasis of the brain. The BBB is formed by tight junctions between endothelial cells lining cerebral microvessels, in addition to pericytes and astrocytes. The BCSFB is formed by tight junctions between (i) epithelial cells at the choroid plexus, (ii) endothelial cells of the veins and venules within the subarachnoid space, and (iii) the epithelial cells of the arachnoid mater. The olfactory system bypasses the cellular barriers of the CNS and provides a direct portal from the nasal cavity to the olfactory bulb within the brain.
Samantha J. Dando et al. Clin. Microbiol. Rev. 2014; doi: /CMR