Methanol meoh

SPL tablets (Splendil^® 2.5 mg tablet, AstraZeneca plc, Cambridge, UK) were purchased from a commercial source. Formic acid (99%) and methanol (MeOH, 99%) were obtained from Fujifilm Wako Pure Chemical Corporation (Osaka, Japan). FL drug substance used as a standard substance was obtained from Tokyo Chemical Industry Co., Ltd. (Tokyo, Japan). All reagents and organic solvents were of special or HPLC grade. Milli-Q (18.2 Ω/cm) water was prepared by using a Milli-Q water purification system (Merck, Darmstadt, Germany).

MEL (Sigma‐Aldrich, St. Louis, MO, USA), AFMK (Cayman Chemical, Ann Arbor, MI, USA), AMK (Toronto Research Chemicals, Toronto, Canada), 6‐hydroxymelatonin (6OHMEL; Sigma‐Aldrich), and isoflurane (Pfizer, Tokyo, Japan) were purchased for this study. Ethanol (EtOH) and dimethyl sulfoxide (DMSO) were supplied by Kanto Chemical (Tokyo, Japan). Acetone, acetic acid, ammonium acetate, and methanol (MeOH) were supplied by Wako (Tokyo, Japan). Milli‐Q water was used in all assays, and all reagents were of analytical grade or higher.
Animals were intraperitoneally treated with MEL (1.0 or 5.0 mg/kg in saline containing 1% EtOH), AFMK (0.1 or 1.0 mg/kg in saline), AMK (0.01, 0.1, or 1.0 mg/kg in saline), or 6OHMEL (1.0 mg/kg in saline containing 1% DMSO) as early as possible before the dark period. To assess inhibition of the MEL‐to‐AMK metabolic pathway, norharmane (Wako Pure Chemical Industries, Osaka, Japan), an indoleamine 2,3‐dioxygenase (IDO) inhibitor, was injected 5 hours before the training phase.