Fig. 8.
Effect of calcitriol treatment on plasma and brain distribution of [13C5]-5-formylTHF in Folr1 KO mice. Plasma (A, ng/mL) and brain tissue (B, ng/g) concentrations were measured over 5 min following an i.v. bolus injection of 0.25 mg/kg [13C5]-5-formylTHF to WT and Folr1 KO mice. (C) Tissue-to-plasma (Cbrain/Cplasma) concentration ratio of injected [13C5]-5-formylTHF was also determined. Results are presented as mean ± SEM (total of 4 animals per group). Asterisk, pound, and dagger symbols represent data points significantly different from untreated WT, untreated Folr1 KO, and vehicle-treated Folr1 KO groups, respectively (*P < 0.05; #P < 0.05; ##P < 0.01; ††P < 0.01).