What resolves this contention: Smith et al. 2017 report no AQP4 effect; Mestre…

What resolves this contention: Smith et al. 2017 report no AQP4 effect; Mestre et al. 2018, a multi-laboratory response study, re-establish AQP4-dependence and attribute discrepancies to anesthesia, age, and tracer-delivery differences. / Aqp4 gene deletion did not impair transport of fluorescent solutes from sub-arachnoid space to brain in mice or rats, arguing against AQP4-dependent glymphatic transport. / Five groups re-examined AQP4; CSF influx is higher in wild-type mice than in four different Aqp4 KO lines and in one line that lacks perivascular AQP4 (Snta1 KO); meta-analysis demonstrated a significant decrease in tracer transport in KO mice and rats compared to controls.