TY - JOUR
T1 - Methamphetamine drinking microstructure in mice bred to drink high or low amounts of methamphetamine
AU - Eastwood, Emily C.
AU - Barkley-Levenson, Amanda M.
AU - Phillips, Tamara J.
N1 - Funding Information:
This work was supported by the Department of Veterans Affairs , and NIH grants T32 DA07262 , P50 DA018165 , and R24 AA020245 .
PY - 2014/10/1
Y1 - 2014/10/1
N2 - Genetic factors likely influence individual sensitivity to positive and negative effects of methamphetamine (MA) and risk for MA dependence. Genetic influence on MA consumption has been confirmed by selectively breeding mouse lines to consume high (MAHDR) or low (MALDR) amounts of MA, using a two-bottle choice MA drinking (MADR) procedure. Here, we employed a lickometer system to characterize the microstructure of MA (20, 40, and 80. mg/l) and water intake in MAHDR and MALDR mice in 4-h limited access sessions, during the initial 4. hours of the dark phase of their 12:12. h light:dark cycle. Licks at one-minute intervals and total volume consumed were recorded, and bout analysis was performed. MAHDR and MALDR mice consumed similar amounts of MA in mg/kg on the first day of access, but MAHDR mice consumed significantly more MA than MALDR mice during all subsequent sessions. The higher MA intake of MAHDR mice was associated with a larger number of MA bouts, longer bout duration, shorter interbout interval, and shorter latency to the first bout. In a separate 4-h limited access MA drinking study, MALDR and MAHDR mice had similar blood MA levels on the first day MA was offered, but MAHDR mice had higher blood MA levels on all subsequent days, which corresponded with MA intake. These data provide insight into the microstructure of MA intake in an animal model of differential genetic risk for MA consumption, which may be pertinent to MA use patterns relevant to genetic risk for MA dependence.
AB - Genetic factors likely influence individual sensitivity to positive and negative effects of methamphetamine (MA) and risk for MA dependence. Genetic influence on MA consumption has been confirmed by selectively breeding mouse lines to consume high (MAHDR) or low (MALDR) amounts of MA, using a two-bottle choice MA drinking (MADR) procedure. Here, we employed a lickometer system to characterize the microstructure of MA (20, 40, and 80. mg/l) and water intake in MAHDR and MALDR mice in 4-h limited access sessions, during the initial 4. hours of the dark phase of their 12:12. h light:dark cycle. Licks at one-minute intervals and total volume consumed were recorded, and bout analysis was performed. MAHDR and MALDR mice consumed similar amounts of MA in mg/kg on the first day of access, but MAHDR mice consumed significantly more MA than MALDR mice during all subsequent sessions. The higher MA intake of MAHDR mice was associated with a larger number of MA bouts, longer bout duration, shorter interbout interval, and shorter latency to the first bout. In a separate 4-h limited access MA drinking study, MALDR and MAHDR mice had similar blood MA levels on the first day MA was offered, but MAHDR mice had higher blood MA levels on all subsequent days, which corresponded with MA intake. These data provide insight into the microstructure of MA intake in an animal model of differential genetic risk for MA consumption, which may be pertinent to MA use patterns relevant to genetic risk for MA dependence.
KW - Amphetamine
KW - Genetics
KW - Lickometer
KW - Limited access
KW - Selective breeding
KW - Two-bottle choice drinking
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U2 - 10.1016/j.bbr.2014.06.035
DO - 10.1016/j.bbr.2014.06.035
M3 - Article
C2 - 24978098
AN - SCOPUS:84904311243
SN - 0166-4328
VL - 272
SP - 111
EP - 120
JO - Behavioural Brain Research
JF - Behavioural Brain Research
ER -