Values substantially greater than ~ 1 µL g−1 min−1 imply that clearance is primarily across the blood–brain barrier rather than via perivascular efflux
aSee Sect. 5.1
bSee Sect. 5.2
cClearance known to be large but difficult to measure
dSee Fig. 8
eSee Sect. 5.3 and Appendix D
fSee Sect. 5.4
gSee Table 1
hNet fluxes at blood–brain barrier 1–20 nmol g−1 min−1, perivascular effluxes (except glutamine) ~ 0.1 nmol g−1 min−1, glutamine ~ 1 nmol g−1 min−1
iSee Appendix E, NKCC1 is the Na+, K+, 2Cl−—cotransporter; jsee Appendix E
kSee Sect. 5.7.3
lSee Appendix B
mNegligible blood–brain barrier clearance, see Sect. 3 and Appendix B