Long-continuous observation of the effects of methamphetamine on wheel-running and drinking in mice.
1. Effects of methamphetamine (MAP) on wheel-running and drinking in mice, housed under 12-hr light-dark schedule (light period; 06:00-18:00), were investigated through long-continuous observation. 2. MAP (1, 2 and 4 mg/kg, s.c.) acutely increased the wheel-running and drinking for 2-4 hr in a dose-dependent manner after the administration at 11:00, midpoint of light period. 3. MAP administered at 11:00 sub-acutely suppressed the spontaneous increment during dark period (18:00-06:00) in both the behaviors. 4. Many factors, such as the time-of-day and interval of the administration as well as the dose administered, affected the behavioral suppression induced by MAP. 5. In addition to these findings, the wheel-running and drinking during the light period increased even on the days without MAP administration. 6. These results suggest that MAP have not only acute stimulant and sub-acute depressant effects, but also long-lasting effects.
Uchihashi
Y
Y
Division for Behavior Analysis, Gunma University School of Medicine, Maebashi, Japan.
Kuribara
H
H
Yasuda
H
H
Umezu
T
T
Tadokoro
S
S
D000818:Animals; D002940:Circadian Rhythm / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004326:Drinking / Q000187:drug effects*; D008297:Male; D008694:Methamphetamine / Q000008:administration & dosage / Q000494:pharmacology*; D051379:Mice; D008815:Mice, Inbred Strains; D009043:Motor Activity / Q000187:drug effects*
D008694:Methamphetamine