Table 1.

Segmental heterogeneity in the brain microvasculature endothelial cells (arterioles, capillaries and venules).

Adapted from [29] and [30]

	Arterioles	Capillaries	References
Cells
Smooth muscle cells	Yes	No	[13, 30]
Pericytes	Yes/No	Yes	[13, 31]
Perivascular macrophages	Yes	Yes	[13, 30]
BBB features
Tight junctions (TJs)	Continuous and elaborate TJs/?	Highly expressed TJs	[29, 32, 33]
Permeability for BBB markers	?	No	[30, 34]
Astrocytic end-foot shealth	No	Yes	[29, 30]
Transporters/enzymes/receptors
P-glycoprotein	?	+++	[35, 36]
Na+/K+-ATPase	+++	+	[29]
Transferrin receptor (TFRC)	–	+++	[13, 37]
Alkaline phosphatase	+++	+++	[29]
Mg2+-ATPase	+++	+	[29]
5′-nucleotidase	+++	+	[29]
γ-Glutamyl transpeptidase (GGTP)	?	+++	[38, 39]
Bidirectiona/l vesicular horsedish peroxidase transport	+++	+	[29, 40]

Presence of perivascular cells is indicated by Yes/No. Presence of BBB features is indicated by Yes/No/non determined (n.d.). Relative expression of transporters/enzymes is indicated by +, ++ or +++ from lowest to highest expression